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math-013301
Number Theory: Congruences — Solving $ax\equiv 1$
7
Give a theorem-based solution: Find the multiplicative inverse of $68$ modulo $517$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{517}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition fo...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(68,517)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such that...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{479}$.\nMethod 1 constructs an inverse via Bézout, producing $x=479$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analysis: Extended Euc...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{479}$.)
math-013302
Computational Number Theory: Inverses and Certificates
7
Explain why your operations are valid: Find the multiplicative inverse of $1124$ modulo $1427$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1427}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient ...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=1281$ and compute $1124x=1439844$.", "Step 2: Reduce: $1439844\\equiv 1\\pmod{1427}$ (since $1439843=143984...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1281}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1281$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity ana...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{1281}$.)
math-013303
Number Theory: Modular Inverses — Extended Euclid
7
Where appropriate, name the theorem you use: Find the multiplicative inverse of $83$ modulo $750$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{750}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficien...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=497$ and compute $83x=41251$.", "Step 2: Reduce: $41251\\equiv 1\\pmod{750}$ (since $41250=41250$ is divisi...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{497}$.\nMethod 1 constructs an inverse via Bézout, producing $x=497$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analysis: Extended Euclid is...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{497}$.)
math-013304
Number Theory: Units mod m — Existence Condition
7
Work this out carefully: Find the multiplicative inverse of $758$ modulo $813$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{813}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an ...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(758,813)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such tha...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{473}$.\nMethod 1 constructs an inverse via Bézout, producing $x=473$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the p...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Takeaway: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013305
Number Theory: Units mod m — Existence Condition
7
Give a theorem-based solution: Find the multiplicative inverse of $427$ modulo $1207$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1207}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(427,1207)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{995}$.\nMethod 1 constructs an inverse via Bézout, producing $x=995$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustness note: ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{995}$.)
math-013306
Number Theory: gcd — Back Substitution
7
Proceed methodically: (a) Compute $\gcd(1142,858)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1142+v\cdot 858=\gcd(1142,858)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include ...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=142$ and $v=-189$ with $u114...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{2}$.\nThe Euclidean algorithm computes $g=2$. The Bézout certificate $u=142,v=-189$ satisfies $u1142+v858=2$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "General...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013307
Computational Number Theory: Inverses and Certificates
7
Provide a rigorous solution: Find the multiplicative inverse of $1156$ modulo $1927$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1927}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition ...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=1922$ and compute $1156x=2221832$.", "Step 2: Reduce: $2221832\\equiv 1\\pmod{1927}$ (since $2221831=222183...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1922}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1922$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analysis: Extended Euclid ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{1922}$.)
math-013308
Number Theory: Bézout Identity — Certificates
7
Start by stating any domain restrictions: (a) Compute $\gcd(801,1771)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 801+v\cdot 1771=\gcd(801,1771)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitut...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(801,1771)$ to compute $g=\\gcd(801,1771)$.", "Step 2: Record the remainder...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-765,v=346$ satisfies $u801+v1771=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Sensitivity analysis: Euclid s...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Takeaway: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013309
Number Theory: Bézout Identity — Certificates
7
Give a fully justified solution: (a) Compute $\gcd(1172,921)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1172+v\cdot 921=\gcd(1172,921)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1172,921)$ to compute $g=\\gcd(1172,921)$.", "Step 2: Record the remainder...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=455,v=-579$ satisfies $u1172+v921=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the ...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013310
Computational Number Theory: Extended Euclid
7
Try to avoid pattern-matching; explain why: (a) Compute $\gcd(1803,866)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1803+v\cdot 866=\gcd(1803,866)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substit...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=61$ and $v=-127$ with $u1803...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=61,v=-127$ satisfies $u1803+v866=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Generali...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Takeaway: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013311
Number Theory: Congruences — Solving $ax\equiv 1$
7
Provide both a computational and a conceptual explanation: Find the multiplicative inverse of $481$ modulo $1016$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1016}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necess...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(481,1016)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{809}$.\nMethod 1 constructs an inverse via Bézout, producing $x=809$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustne...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013312
Number Theory: Modular Inverses — Extended Euclid
7
Answer with a short justification: Find the multiplicative inverse of $99$ modulo $1802$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1802}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condit...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=1711$ and compute $99x=169389$.", "Step 2: Reduce: $169389\\equiv 1\\pmod{1802}$ (since $169388=169388$ is ...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1711}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1711$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustness note: Extended Euclid is fa...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013313
Number Theory: gcd — Back Substitution
7
Use two approaches if possible: (a) Compute $\gcd(776,180)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 776+v\cdot 180=\gcd(776,180)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. I...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-16$ and $v=69$ with $u776+v...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{4}$.\nThe Euclidean algorithm computes $g=4$. The Bézout certificate $u=-16,v=69$ satisfies $u776+v180=4$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustness note: Euclid scales ef...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Remember: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013314
Number Theory: Congruences — Solving $ax\equiv 1$
7
Give an answer and a quick verification: Find the multiplicative inverse of $897$ modulo $1730$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1730}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(897,1730)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1703}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1703$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analysis: Extended Euclid ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Takeaway: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013315
Number Theory: Units mod m — Existence Condition
7
Give a fully justified solution: Find the multiplicative inverse of $656$ modulo $705$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{705}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=446$ and compute $656x=292576$.", "Step 2: Reduce: $292576\\equiv 1\\pmod{705}$ (since $292575=292575$ is d...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{446}$.\nMethod 1 constructs an inverse via Bézout, producing $x=446$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Generality note: ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Takeaway: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{446}$.)
math-013316
Number Theory: Modular Inverses — Extended Euclid
7
Use two approaches if possible: Find the multiplicative inverse of $75$ modulo $347$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{347}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition f...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=310$ and compute $75x=23250$.", "Step 2: Reduce: $23250\\equiv 1\\pmod{347}$ (since $23249=23249$ is divisi...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{310}$.\nMethod 1 constructs an inverse via Bézout, producing $x=310$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustne...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{310}$.)
math-013317
Number Theory: gcd — Back Substitution
7
Determine the requested value: (a) Compute $\gcd(1605,1895)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1605+v\cdot 1895=\gcd(1605,1895)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chai...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1605,1895)$ to compute $g=\\gcd(1605,1895)$.", "Step 2: Record the remaind...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{5}$.\nThe Euclidean algorithm computes $g=5$. The Bézout certificate $u=98,v=-83$ satisfies $u1605+v1895=5$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the problem were pertu...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Takeaway: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{5}$.)
math-013318
Number Theory: gcd — Back Substitution
7
Keep the final answer in boxed form: (a) Compute $\gcd(1855,1414)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1855+v\cdot 1414=\gcd(1855,1414)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitutio...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=93$ and $v=-122$ with $u1855...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{7}$.\nThe Euclidean algorithm computes $g=7$. The Bézout certificate $u=93,v=-122$ satisfies $u1855+v1414=7$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Sensitivity analysis: Euclid s...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013319
Number Theory: Congruences — Solving $ax\equiv 1$
7
Determine the requested value: Find the multiplicative inverse of $417$ modulo $950$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{950}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition f...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(417,950)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such tha...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{303}$.\nMethod 1 constructs an inverse via Bézout, producing $x=303$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustness note: Extended Euclid i...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013320
Number Theory: Units mod m — Existence Condition
7
Provide a rigorous solution: Find the multiplicative inverse of $458$ modulo $591$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{591}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(458,591)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such tha...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{551}$.\nMethod 1 constructs an inverse via Bézout, producing $x=551$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the problem were perturbed: Ext...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013321
Number Theory: gcd — Back Substitution
7
Use two approaches if possible: (a) Compute $\gcd(1551,947)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1551+v\cdot 947=\gcd(1551,947)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain....
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1551,947)$ to compute $g=\\gcd(1551,947)$.", "Step 2: Record the remainder...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=127,v=-208$ satisfies $u1551+v947=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the problem were pert...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013322
Number Theory: gcd — Back Substitution
7
Indicate where a theorem is used: (a) Compute $\gcd(1467,1432)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1467+v\cdot 1432=\gcd(1467,1432)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution c...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1467,1432)$ to compute $g=\\gcd(1467,1432)$.", "Step 2: Record the remaind...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=491,v=-503$ satisfies $u1467+v1432=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the problem were per...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013323
Number Theory: Congruences — Solving $ax\equiv 1$
7
Solve and then verify: Find the multiplicative inverse of $39$ modulo $881$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{881}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an inv...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(39,881)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such that...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{497}$.\nMethod 1 constructs an inverse via Bézout, producing $x=497$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the problem were perturbed: Extended ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{497}$.)
math-013324
Number Theory: Congruences — Solving $ax\equiv 1$
7
Compute the requested quantity: Find the multiplicative inverse of $494$ modulo $1909$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1909}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient conditio...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=228$ and compute $494x=112632$.", "Step 2: Reduce: $112632\\equiv 1\\pmod{1909}$ (since $112631=112631$ is ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{228}$.\nMethod 1 constructs an inverse via Bézout, producing $x=228$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitiv...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013325
Number Theory: Congruences — Solving $ax\equiv 1$
7
Answer with a short justification: Find the multiplicative inverse of $844$ modulo $1189$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1189}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condi...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=996$ and compute $844x=840624$.", "Step 2: Reduce: $840624\\equiv 1\\pmod{1189}$ (since $840623=840623$ is ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{996}$.\nMethod 1 constructs an inverse via Bézout, producing $x=996$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Generality note: ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{996}$.)
math-013326
Number Theory: gcd — Euclidean Algorithm
7
Solve and then verify: (a) Compute $\gcd(1551,1483)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1551+v\cdot 1483=\gcd(1551,1483)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Incl...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1551,1483)$ to compute $g=\\gcd(1551,1483)$.", "Step 2: Record the remaind...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=458,v=-479$ satisfies $u1551+v1483=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustness note: Euclid...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013327
Number Theory: Bézout Identity — Certificates
7
Solve and then verify: (a) Compute $\gcd(1889,1171)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1889+v\cdot 1171=\gcd(1889,1171)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Incl...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1889,1171)$ to compute $g=\\gcd(1889,1171)$.", "Step 2: Record the remaind...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-517,v=834$ satisfies $u1889+v1171=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustness note: Euclid scale...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013328
Number Theory: gcd — Euclidean Algorithm
7
State any required conditions first: (a) Compute $\gcd(1705,1615)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1705+v\cdot 1615=\gcd(1705,1615)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitutio...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=18$ and $v=-19$ with $u1705+...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{5}$.\nThe Euclidean algorithm computes $g=5$. The Bézout certificate $u=18,v=-19$ satisfies $u1705+v1615=5$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Generality note: Euclid s...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Remember: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013329
Computational Number Theory: Extended Euclid
7
Prompt: (a) Compute $\gcd(958,1154)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 958+v\cdot 1154=\gcd(958,1154)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include a brief verifi...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-53$ and $v=44$ with $u958+v...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{2}$.\nThe Euclidean algorithm computes $g=2$. The Bézout certificate $u=-53,v=44$ satisfies $u958+v1154=2$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{2}$.)
math-013330
Number Theory: Congruences — Solving $ax\equiv 1$
7
Warm-up: Find the multiplicative inverse of $835$ modulo $1751$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1751}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an inverse to exi...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=281$ and compute $835x=234635$.", "Step 2: Reduce: $234635\\equiv 1\\pmod{1751}$ (since $234634=234634$ is ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{281}$.\nMethod 1 constructs an inverse via Bézout, producing $x=281$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the problem were perturbed: Ext...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{281}$.)
math-013331
Number Theory: Congruences — Solving $ax\equiv 1$
7
Provide a rigorous solution: Find the multiplicative inverse of $343$ modulo $559$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{559}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(343,559)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such tha...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{515}$.\nMethod 1 constructs an inverse via Bézout, producing $x=515$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustness note: Extended Euclid i...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013332
Number Theory: gcd — Back Substitution
7
Give reasoning, not just computation: (a) Compute $\gcd(441,1837)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 441+v\cdot 1837=\gcd(441,1837)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution ...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(441,1837)$ to compute $g=\\gcd(441,1837)$.", "Step 2: Record the remainder...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-604,v=145$ satisfies $u441+v1837=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "General...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013333
Number Theory: Modular Inverses — Extended Euclid
7
State any required conditions first: Find the multiplicative inverse of $5$ modulo $69$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{69}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=14$ and compute $5x=70$.", "Step 2: Reduce: $70\\equiv 1\\pmod{69}$ (since $69=69$ is divisible by 69).", ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{14}$.\nMethod 1 constructs an inverse via Bézout, producing $x=14$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analysis: Extended Eucli...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{14}$.)
math-013334
Number Theory: Units mod m — Existence Condition
7
Solve and justify each step: Find the multiplicative inverse of $273$ modulo $314$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{314}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(273,314)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such tha...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{291}$.\nMethod 1 constructs an inverse via Bézout, producing $x=291$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analysis: Extended Euc...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013335
Computational Number Theory: Extended Euclid
7
Task: (a) Compute $\gcd(356,1849)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 356+v\cdot 1849=\gcd(356,1849)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include a brief verifica...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-670$ and $v=129$ with $u356...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-670,v=129$ satisfies $u356+v1849=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Sensiti...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Remember: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013336
Number Theory: Modular Inverses — Extended Euclid
7
Start by stating any domain restrictions: Find the multiplicative inverse of $41$ modulo $122$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{122}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient c...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(41,122)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such that...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{3}$.\nMethod 1 constructs an inverse via Bézout, producing $x=3$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Generality n...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{3}$.)
math-013337
Number Theory: Units mod m — Existence Condition
7
Where appropriate, name the theorem you use: Find the multiplicative inverse of $757$ modulo $1505$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1505}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and suffic...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(757,1505)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1338}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1338$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Generality note...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013338
Number Theory: gcd — Back Substitution
7
Solve and then verify: (a) Compute $\gcd(820,1913)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 820+v\cdot 1913=\gcd(820,1913)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(820,1913)$ to compute $g=\\gcd(820,1913)$.", "Step 2: Record the remainder...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=7,v=-3$ satisfies $u820+v1913=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Se...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013339
Number Theory: Divisibility — Linear Combinations
7
Solve with verification: (a) Compute $\gcd(678,1158)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 678+v\cdot 1158=\gcd(678,1158)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Inclu...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=41$ and $v=-24$ with $u678+v...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{6}$.\nThe Euclidean algorithm computes $g=6$. The Bézout certificate $u=41,v=-24$ satisfies $u678+v1158=6$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Sensitivity analysis: Euclid sca...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Takeaway: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{6}$.)
math-013340
Number Theory: Congruences — Solving $ax\equiv 1$
7
Carefully track domains: Find the multiplicative inverse of $62$ modulo $761$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{761}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an i...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=626$ and compute $62x=38812$.", "Step 2: Reduce: $38812\\equiv 1\\pmod{761}$ (since $38811=38811$ is divisi...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{626}$.\nMethod 1 constructs an inverse via Bézout, producing $x=626$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Generali...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013341
Number Theory: gcd — Euclidean Algorithm
7
Keep the final answer in boxed form: (a) Compute $\gcd(209,1264)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 209+v\cdot 1264=\gcd(209,1264)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution c...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-127$ and $v=21$ with $u209+...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-127,v=21$ satisfies $u209+v1264=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the problem were perturbed: ...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013342
Number Theory: Congruences — Solving $ax\equiv 1$
7
Where appropriate, name the theorem you use: Find the multiplicative inverse of $25$ modulo $161$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{161}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficien...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(25,161)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such that...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{58}$.\nMethod 1 constructs an inverse via Bézout, producing $x=58$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the pro...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013343
Number Theory: gcd — Back Substitution
7
Solve and then verify: (a) Compute $\gcd(1594,938)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1594+v\cdot 938=\gcd(1594,938)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1594,938)$ to compute $g=\\gcd(1594,938)$.", "Step 2: Record the remainder...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{2}$.\nThe Euclidean algorithm computes $g=2$. The Bézout certificate $u=153,v=-260$ satisfies $u1594+v938=2$, and divisibility shows no larger common divisor can exist.", "robustness_analysis":...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{2}$.)
math-013344
Number Theory: Modular Inverses — Extended Euclid
7
Work this out carefully: Find the multiplicative inverse of $938$ modulo $1165$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1165}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for a...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(938,1165)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{272}$.\nMethod 1 constructs an inverse via Bézout, producing $x=272$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitiv...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{272}$.)
math-013345
Computational Number Theory: Extended Euclid
7
Work carefully and justify each inference: (a) Compute $\gcd(727,126)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 727+v\cdot 126=\gcd(727,126)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitutio...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=13$ and $v=-75$ with $u727+v...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=13,v=-75$ satisfies $u727+v126=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustness...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Remember: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013346
Number Theory: Congruences — Solving $ax\equiv 1$
7
Work this out carefully: Find the multiplicative inverse of $348$ modulo $353$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{353}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an ...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(348,353)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such tha...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{141}$.\nMethod 1 constructs an inverse via Bézout, producing $x=141$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustness note: ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Takeaway: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{141}$.)
math-013347
Computational Number Theory: Extended Euclid
7
Work carefully and justify each inference: (a) Compute $\gcd(1673,1519)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1673+v\cdot 1519=\gcd(1673,1519)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-subst...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-69$ and $v=76$ with $u1673+...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{7}$.\nThe Euclidean algorithm computes $g=7$. The Bézout certificate $u=-69,v=76$ satisfies $u1673+v1519=7$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustne...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{7}$.)
math-013348
Number Theory: Units mod m — Existence Condition
7
Derive the result step-by-step: Find the multiplicative inverse of $634$ modulo $1141$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1141}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient conditio...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(634,1141)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{9}$.\nMethod 1 constructs an inverse via Bézout, producing $x=9$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustness note: Extended Euclid is fa...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013349
Computational Number Theory: Extended Euclid
7
Indicate where a theorem is used: (a) Compute $\gcd(866,1837)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 866+v\cdot 1837=\gcd(866,1837)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chai...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(866,1837)$ to compute $g=\\gcd(866,1837)$.", "Step 2: Record the remainder...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-70,v=33$ satisfies $u866+v1837=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Generalit...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Remember: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013350
Number Theory: gcd — Back Substitution
7
State any required conditions first: (a) Compute $\gcd(1241,536)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1241+v\cdot 536=\gcd(1241,536)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution c...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1241,536)$ to compute $g=\\gcd(1241,536)$.", "Step 2: Record the remainder...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-111,v=257$ satisfies $u1241+v536=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Generality note: Euclid ...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013351
Number Theory: Modular Inverses — Extended Euclid
7
Warm-up: Find the multiplicative inverse of $236$ modulo $1783$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1783}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an inverse to exi...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=68$ and compute $236x=16048$.", "Step 2: Reduce: $16048\\equiv 1\\pmod{1783}$ (since $16047=16047$ is divis...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{68}$.\nMethod 1 constructs an inverse via Bézout, producing $x=68$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analysis: Extended Eucli...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013352
Number Theory: Divisibility — Linear Combinations
7
Problem: (a) Compute $\gcd(1625,1001)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1625+v\cdot 1001=\gcd(1625,1001)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include a brief ve...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-8$ and $v=13$ with $u1625+v...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{13}$.\nThe Euclidean algorithm computes $g=13$. The Bézout certificate $u=-8,v=13$ satisfies $u1625+v1001=13$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the problem were per...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{13}$.)
math-013353
Number Theory: Bézout Identity — Certificates
7
Exercise: (a) Compute $\gcd(897,514)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 897+v\cdot 514=\gcd(897,514)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include a brief verific...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(897,514)$ to compute $g=\\gcd(897,514)$.", "Step 2: Record the remainder e...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=51,v=-89$ satisfies $u897+v514=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustness note: Euclid sca...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013354
Number Theory: Modular Inverses — Extended Euclid
7
Explain why your operations are valid: Find the multiplicative inverse of $803$ modulo $1810$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1810}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient c...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=417$ and compute $803x=334851$.", "Step 2: Reduce: $334851\\equiv 1\\pmod{1810}$ (since $334850=334850$ is ...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{417}$.\nMethod 1 constructs an inverse via Bézout, producing $x=417$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the p...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{417}$.)
math-013355
Number Theory: Divisibility — Linear Combinations
7
Use two approaches if possible: (a) Compute $\gcd(137,689)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 137+v\cdot 689=\gcd(137,689)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. I...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(137,689)$ to compute $g=\\gcd(137,689)$.", "Step 2: Record the remainder e...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=171,v=-34$ satisfies $u137+v689=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the pr...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013356
Number Theory: gcd — Euclidean Algorithm
7
Give an answer and a quick verification: (a) Compute $\gcd(403,379)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 403+v\cdot 379=\gcd(403,379)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution ...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(403,379)$ to compute $g=\\gcd(403,379)$.", "Step 2: Record the remainder e...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=79,v=-84$ satisfies $u403+v379=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustness note: Euclid scales ef...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Remember: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013357
Number Theory: Modular Inverses — Extended Euclid
7
Write the solution set clearly: Find the multiplicative inverse of $267$ modulo $347$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{347}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition ...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=13$ and compute $267x=3471$.", "Step 2: Reduce: $3471\\equiv 1\\pmod{347}$ (since $3470=3470$ is divisible ...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{13}$.\nMethod 1 constructs an inverse via Bézout, producing $x=13$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the problem were...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{13}$.)
math-013358
Number Theory: Divisibility — Linear Combinations
7
Checkpoint: (a) Compute $\gcd(1689,1643)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1689+v\cdot 1643=\gcd(1689,1643)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include a brief...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1689,1643)$ to compute $g=\\gcd(1689,1643)$.", "Step 2: Record the remaind...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-250,v=257$ satisfies $u1689+v1643=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis"...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013359
Number Theory: gcd — Back Substitution
7
Proceed methodically: (a) Compute $\gcd(396,441)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 396+v\cdot 441=\gcd(396,441)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include a b...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(396,441)$ to compute $g=\\gcd(396,441)$.", "Step 2: Record the remainder e...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{9}$.\nThe Euclidean algorithm computes $g=9$. The Bézout certificate $u=-10,v=9$ satisfies $u396+v441=9$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Sensitivity analysis: Euclid scale...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{9}$.)
math-013360
Computational Number Theory: Inverses and Certificates
7
Derive the result step-by-step: Find the multiplicative inverse of $127$ modulo $138$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{138}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition ...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(127,138)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such tha...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{25}$.\nMethod 1 constructs an inverse via Bézout, producing $x=25$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivit...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{25}$.)
math-013361
Computational Number Theory: Extended Euclid
7
Use two approaches if possible: (a) Compute $\gcd(256,746)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 256+v\cdot 746=\gcd(256,746)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. I...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=102$ and $v=-35$ with $u256+...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{2}$.\nThe Euclidean algorithm computes $g=2$. The Bézout certificate $u=102,v=-35$ satisfies $u256+v746=2$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Generality note: Euclid sc...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013362
Number Theory: Divisibility — Linear Combinations
7
Write the solution set clearly: (a) Compute $\gcd(1580,221)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1580+v\cdot 221=\gcd(1580,221)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain....
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=67$ and $v=-479$ with $u1580...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=67,v=-479$ satisfies $u1580+v221=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustne...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013363
Number Theory: Modular Inverses — Extended Euclid
7
Answer using clear logical steps: Find the multiplicative inverse of $371$ modulo $921$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{921}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient conditio...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=638$ and compute $371x=236698$.", "Step 2: Reduce: $236698\\equiv 1\\pmod{921}$ (since $236697=236697$ is d...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{638}$.\nMethod 1 constructs an inverse via Bézout, producing $x=638$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustne...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{638}$.)
math-013364
Number Theory: Modular Inverses — Extended Euclid
7
Solve and then verify: Find the multiplicative inverse of $662$ modulo $1101$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1101}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an ...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(662,1101)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{158}$.\nMethod 1 constructs an inverse via Bézout, producing $x=158$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Generality note: Extended Euclid is fast...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{158}$.)
math-013365
Number Theory: Divisibility — Linear Combinations
7
Solve and justify each step: (a) Compute $\gcd(829,531)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 829+v\cdot 531=\gcd(829,531)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Incl...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-98$ and $v=153$ with $u829+...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-98,v=153$ satisfies $u829+v531=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Generality note: Euclid sc...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013366
Number Theory: Congruences — Solving $ax\equiv 1$
7
Checkpoint: Find the multiplicative inverse of $44$ modulo $1861$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1861}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an inverse to e...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=1142$ and compute $44x=50248$.", "Step 2: Reduce: $50248\\equiv 1\\pmod{1861}$ (since $50247=50247$ is divi...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{1142}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1142$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Generality note...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{1142}$.)
math-013367
Number Theory: Congruences — Solving $ax\equiv 1$
7
Solve and justify each step: Find the multiplicative inverse of $40$ modulo $1669$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1669}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition fo...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=459$ and compute $40x=18360$.", "Step 2: Reduce: $18360\\equiv 1\\pmod{1669}$ (since $18359=18359$ is divis...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{459}$.\nMethod 1 constructs an inverse via Bézout, producing $x=459$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Generality note: ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Takeaway: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{459}$.)
math-013368
Computational Number Theory: Extended Euclid
7
Solve (and briefly cross-validate): (a) Compute $\gcd(1438,974)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1438+v\cdot 974=\gcd(1438,974)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution ch...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1438,974)$ to compute $g=\\gcd(1438,974)$.", "Step 2: Record the remainder...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{2}$.\nThe Euclidean algorithm computes $g=2$. The Bézout certificate $u=-233,v=344$ satisfies $u1438+v974=2$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "General...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{2}$.)
math-013369
Computational Number Theory: Inverses and Certificates
7
Write the solution set clearly: Find the multiplicative inverse of $1721$ modulo $1759$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1759}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient conditi...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(1721,1759)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such t...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{324}$.\nMethod 1 constructs an inverse via Bézout, producing $x=324$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analy...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013370
Number Theory: Modular Inverses — Extended Euclid
7
Start by stating any domain restrictions: Find the multiplicative inverse of $475$ modulo $1259$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1259}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficien...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(475,1259)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{493}$.\nMethod 1 constructs an inverse via Bézout, producing $x=493$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the problem were perturbed: Ext...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013371
Number Theory: Modular Inverses — Extended Euclid
7
Do not skip justification steps: Find the multiplicative inverse of $1349$ modulo $1455$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1455}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condit...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=1304$ and compute $1349x=1759096$.", "Step 2: Reduce: $1759096\\equiv 1\\pmod{1455}$ (since $1759095=175909...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1304}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1304$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Genera...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Takeaway: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013372
Number Theory: Congruences — Solving $ax\equiv 1$
7
Start by stating any domain restrictions: Find the multiplicative inverse of $767$ modulo $1880$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1880}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficien...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=1103$ and compute $767x=846001$.", "Step 2: Reduce: $846001\\equiv 1\\pmod{1880}$ (since $846000=846000$ is...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1103}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1103$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analysis: Extended Euclid ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{1103}$.)
math-013373
Number Theory: Congruences — Solving $ax\equiv 1$
7
Task: Find the multiplicative inverse of $1253$ modulo $1607$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1607}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an inverse to exist...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=976$ and compute $1253x=1222928$.", "Step 2: Reduce: $1222928\\equiv 1\\pmod{1607}$ (since $1222927=1222927...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{976}$.\nMethod 1 constructs an inverse via Bézout, producing $x=976$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the problem were perturbed: Extended ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Takeaway: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{976}$.)
math-013374
Number Theory: Units mod m — Existence Condition
7
Try to avoid pattern-matching; explain why: Find the multiplicative inverse of $141$ modulo $695$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{695}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficien...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=626$ and compute $141x=88266$.", "Step 2: Reduce: $88266\\equiv 1\\pmod{695}$ (since $88265=88265$ is divis...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{626}$.\nMethod 1 constructs an inverse via Bézout, producing $x=626$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustness note: ...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{626}$.)
math-013375
Number Theory: Divisibility — Linear Combinations
7
Do not skip justification steps: (a) Compute $\gcd(887,162)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 887+v\cdot 162=\gcd(887,162)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. ...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-61$ and $v=334$ with $u887+...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-61,v=334$ satisfies $u887+v162=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013376
Number Theory: Modular Inverses — Extended Euclid
7
Find the exact value: Find the multiplicative inverse of $821$ modulo $855$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{855}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an inv...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=176$ and compute $821x=144496$.", "Step 2: Reduce: $144496\\equiv 1\\pmod{855}$ (since $144495=144495$ is d...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{176}$.\nMethod 1 constructs an inverse via Bézout, producing $x=176$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Generality note: Extended Euclid is fast...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{176}$.)
math-013377
Computational Number Theory: Extended Euclid
7
Show all reasoning: (a) Compute $\gcd(1062,1533)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1062+v\cdot 1533=\gcd(1062,1533)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Include...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-166$ and $v=115$ with $u106...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{3}$.\nThe Euclidean algorithm computes $g=3$. The Bézout certificate $u=-166,v=115$ satisfies $u1062+v1533=3$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Sensit...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013378
Number Theory: gcd — Euclidean Algorithm
7
Solve with verification: (a) Compute $\gcd(1650,1066)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1650+v\cdot 1066=\gcd(1650,1066)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. In...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=115$ and $v=-178$ with $u165...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{2}$.\nThe Euclidean algorithm computes $g=2$. The Bézout certificate $u=115,v=-178$ satisfies $u1650+v1066=2$, and divisibility shows no larger common divisor can exist.", "robustness_analysis"...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{2}$.)
math-013379
Number Theory: Modular Inverses — Extended Euclid
7
Show all reasoning: Find the multiplicative inverse of $202$ modulo $1687$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1687}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an inv...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(202,1687)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1378}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1378$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the problem were perturbed: E...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{1378}$.)
math-013380
Number Theory: Modular Inverses — Extended Euclid
7
Work carefully and justify each inference: Find the multiplicative inverse of $1214$ modulo $1269$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1269}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and suffici...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=323$ and compute $1214x=392122$.", "Step 2: Reduce: $392122\\equiv 1\\pmod{1269}$ (since $392121=392121$ is...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{323}$.\nMethod 1 constructs an inverse via Bézout, producing $x=323$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the p...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{323}$.)
math-013381
Number Theory: Congruences — Solving $ax\equiv 1$
7
Derive the result step-by-step: Find the multiplicative inverse of $1100$ modulo $1233$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1233}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient conditi...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=788$ and compute $1100x=866800$.", "Step 2: Reduce: $866800\\equiv 1\\pmod{1233}$ (since $866799=866799$ is...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{788}$.\nMethod 1 constructs an inverse via Bézout, producing $x=788$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analy...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013382
Number Theory: Congruences — Solving $ax\equiv 1$
7
Indicate where a theorem is used: Find the multiplicative inverse of $1591$ modulo $1940$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1940}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condi...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(1591,1940)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such t...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1751}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1751$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robust...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Takeaway: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{1751}$.)
math-013383
Computational Number Theory: Inverses and Certificates
7
Indicate where a theorem is used: Find the multiplicative inverse of $8$ modulo $99$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{99}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition fo...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(8,99)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such that $...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{62}$.\nMethod 1 constructs an inverse via Bézout, producing $x=62$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustness note: Ex...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{62}$.)
math-013384
Number Theory: Divisibility — Linear Combinations
7
Where appropriate, name the theorem you use: (a) Compute $\gcd(1803,1606)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1803+v\cdot 1606=\gcd(1803,1606)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-sub...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1803,1606)$ to compute $g=\\gcd(1803,1606)$.", "Step 2: Record the remaind...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-375,v=421$ satisfies $u1803+v1606=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustness note: Euclid scale...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Remember: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013385
Number Theory: Units mod m — Existence Condition
7
Give a theorem-based solution: Find the multiplicative inverse of $107$ modulo $1773$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1773}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(107,1773)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{116}$.\nMethod 1 constructs an inverse via Bézout, producing $x=116$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustne...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{116}$.)
math-013386
Number Theory: Divisibility — Linear Combinations
7
Make each step logically reversible (or explain if not): (a) Compute $\gcd(1448,1190)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1448+v\cdot 1190=\gcd(1448,1190)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear ...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-226$ and $v=275$ with $u144...
{ "consistency_check": "Cross-check: both derivations land on the same invariant quantity. Final answer: $\\boxed{2}$.\nThe Euclidean algorithm computes $g=2$. The Bézout certificate $u=-226,v=275$ satisfies $u1448+v1190=2$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Genera...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{2}$.)
math-013387
Number Theory: Congruences — Solving $ax\equiv 1$
7
Solve and then verify: Find the multiplicative inverse of $163$ modulo $454$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{454}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an in...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(163,454)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such tha...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{39}$.\nMethod 1 constructs an inverse via Bézout, producing $x=39$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the pro...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013388
Number Theory: Bézout Identity — Certificates
7
Carefully track domains: (a) Compute $\gcd(430,1106)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 430+v\cdot 1106=\gcd(430,1106)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Inclu...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-18$ and $v=7$ with $u430+v1...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{2}$.\nThe Euclidean algorithm computes $g=2$. The Bézout certificate $u=-18,v=7$ satisfies $u430+v1106=2$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the problem were perturbed: Eu...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Remember: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013389
Computational Number Theory: Inverses and Certificates
7
Determine the requested value: Find the multiplicative inverse of $186$ modulo $1183$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1183}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(186,1183)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such th...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1024}$.\nMethod 1 constructs an inverse via Bézout, producing $x=1024$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Robustness note: Extended Euclid...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Core principle: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{1024}$.)
math-013390
Number Theory: gcd — Back Substitution
7
Derive the result step-by-step: (a) Compute $\gcd(1106,496)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1106+v\cdot 496=\gcd(1106,496)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain....
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1106,496)$ to compute $g=\\gcd(1106,496)$.", "Step 2: Record the remainder...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{2}$.\nThe Euclidean algorithm computes $g=2$. The Bézout certificate $u=-87,v=194$ satisfies $u1106+v496=2$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Robustness note: Euclid s...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{2}$.)
math-013391
Computational Number Theory: Inverses and Certificates
7
Compute the requested quantity: Find the multiplicative inverse of $409$ modulo $412$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{412}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition ...
[ { "method_name": "Extended Euclidean Algorithm", "approach": "Use Bézout: find $u,v$ with $au+mv=1$, then $u$ is an inverse of $a$ modulo $m$.", "steps": [ "Step 1: Check $\\gcd(409,412)=1$, so an inverse exists.", "Step 2: Use the extended Euclidean algorithm to find integers $u,v$ such tha...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{137}$.\nMethod 1 constructs an inverse via Bézout, producing $x=137$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the p...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Remember: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{137}$.)
math-013392
Computational Number Theory: Extended Euclid
7
Do not skip justification steps: (a) Compute $\gcd(1623,763)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1623+v\cdot 763=\gcd(1623,763)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(1623,763)$ to compute $g=\\gcd(1623,763)$.", "Step 2: Record the remainder...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=118,v=-251$ satisfies $u1623+v763=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the problem were pert...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013393
Number Theory: Congruences — Solving $ax\equiv 1$
7
Start by stating any domain restrictions: Find the multiplicative inverse of $19$ modulo $167$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{167}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient c...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=44$ and compute $19x=836$.", "Step 2: Reduce: $836\\equiv 1\\pmod{167}$ (since $835=835$ is divisible by 16...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{44}$.\nMethod 1 constructs an inverse via Bézout, producing $x=44$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivity analysis: Extended Euclid is f...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.
math-013394
Number Theory: gcd — Back Substitution
7
Carefully track domains: (a) Compute $\gcd(1298,689)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1298+v\cdot 689=\gcd(1298,689)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Inclu...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-267$ and $v=503$ with $u129...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-267,v=503$ satisfies $u1298+v689=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the problem were perturbed:...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$.
math-013395
Number Theory: Modular Inverses — Extended Euclid
7
Question: Find the multiplicative inverse of $60$ modulo $169$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{169}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condition for an inverse to exist...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=31$ and compute $60x=1860$.", "Step 2: Reduce: $1860\\equiv 1\\pmod{169}$ (since $1859=1859$ is divisible b...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{31}$.\nMethod 1 constructs an inverse via Bézout, producing $x=31$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "Sensitivit...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout. (Here the result is $\boxed{31}$.)
math-013396
Computational Number Theory: Extended Euclid
7
Track quantifiers carefully: (a) Compute $\gcd(149,700)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 149+v\cdot 700=\gcd(149,700)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Incl...
[ { "method_name": "Euclidean Algorithm + Back-Substitution", "approach": "Compute the gcd by repeated division, then reverse the steps to express the gcd as a linear combination.", "steps": [ "Step 1: Apply Euclid to $(149,700)$ to compute $g=\\gcd(149,700)$.", "Step 2: Record the remainder e...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=249,v=-53$ satisfies $u149+v700=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Sensitivity analysis: Euclid sca...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Core principle: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013397
Computational Number Theory: Extended Euclid
7
Proceed methodically: (a) Compute $\gcd(1062,1293)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1062+v\cdot 1293=\gcd(1062,1293)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain. Inclu...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-28$ and $v=23$ with $u1062+...
{ "consistency_check": "Both approaches agree after simplification. Final answer: $\\boxed{3}$.\nThe Euclidean algorithm computes $g=3$. The Bézout certificate $u=-28,v=23$ satisfies $u1062+v1293=3$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "If the problem were perturbed: ...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Remember: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{3}$.)
math-013398
Number Theory: gcd — Back Substitution
7
Write the solution set clearly: (a) Compute $\gcd(820,1321)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 820+v\cdot 1321=\gcd(820,1321)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear backward-substitution chain....
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-646$ and $v=401$ with $u820...
{ "consistency_check": "Consistency verification shows both paths yield the identical boxed result. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-646,v=401$ satisfies $u820+v1321=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis":...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Takeaway: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013399
Number Theory: Divisibility — Linear Combinations
7
Make each step logically reversible (or explain if not): (a) Compute $\gcd(1108,1049)$ using the Euclidean algorithm. (b) Find integers $u,v$ such that $u\cdot 1108+v\cdot 1049=\gcd(1108,1049)$. (c) Briefly explain why your coefficients certify the gcd. You must show the Euclidean algorithm remainder steps or a clear ...
[ { "method_name": "Bézout + Divisibility Argument", "approach": "Use the definition of gcd as the smallest positive linear combination and show any common divisor divides your combination.", "steps": [ "Step 1: From the extended Euclidean algorithm we obtain integers $u=-160$ and $v=169$ with $u110...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{1}$.\nThe Euclidean algorithm computes $g=1$. The Bézout certificate $u=-160,v=169$ satisfies $u1108+v1049=1$, and divisibility shows no larger common divisor can exist.", "robustness_analysis": "Sensitivity analysis: E...
[ { "error_description": "Stopped Euclid early and used the last remainder before reaching 0.", "why_plausible": "The repeated division process is easy to truncate accidentally.", "why_wrong": "The gcd is the last nonzero remainder; stopping early yields a multiple of the gcd, not necessarily the gcd.", ...
Key idea: The Euclidean algorithm computes gcds efficiently, and Bézout coefficients $u,v$ certify the result because every common divisor must divide $ua+vb=g$. (Here the result is $\boxed{1}$.)
math-013400
Number Theory: Modular Inverses — Extended Euclid
7
Answer with a short justification: Find the multiplicative inverse of $289$ modulo $1293$ (i.e., find an integer $x$ such that $ax\equiv 1\pmod{1293}$). (a) Solve using the extended Euclidean algorithm. (b) Give an independent verification by checking the congruence. (c) Briefly state the necessary and sufficient condi...
[ { "method_name": "Uniqueness + Direct Check", "approach": "Solve by finding any $x$ that works and use uniqueness of inverses modulo $m$ to certify it.", "steps": [ "Step 1: Propose $x=604$ and compute $289x=174556$.", "Step 2: Reduce: $174556\\equiv 1\\pmod{1293}$ (since $174555=174555$ is ...
{ "consistency_check": "The two methods are consistent and must coincide. Final answer: $\\boxed{604}$.\nMethod 1 constructs an inverse via Bézout, producing $x=604$. Method 2 verifies $ax\\equiv 1$ directly and uses uniqueness, so both necessarily agree.", "robustness_analysis": "If the problem were perturbed: Ext...
[ { "error_description": "Tried to invert even when $\\gcd(a,m)\\ne 1$.", "why_plausible": "The inverse notation $a^{-1}$ suggests it always exists.", "why_wrong": "If $d=\\gcd(a,m)>1$, then $ax$ is always divisible by $d$ modulo $m$, so it cannot be congruent to 1.", "which_method_catches_it": "Exten...
Key idea: A modular inverse exists iff $\gcd(a,m)=1$. Extended Euclid constructs it and also provides a proof certificate via Bézout.