content string | quality_label int64 | meta string | all-MiniLM-L6-v2_embedding list | doc_id int64 | unique_id string |
|---|---|---|---|---|---|
When is this map completely positive?
up vote 4 down vote favorite
5
Consider the complex $n$-by-$n$ matrices $M_n$. Suppose that $A_i$, for $i=1,\ldots,n^2$, satisfy $\mathrm{Tr}(A_i^* A_j)=\delta_{ij}$, so that together they form an orthonormal basis for $M_n$.
Define a linear map $T \colon M_n \to M_n \otimes M_n$ ... | 5 | [
-0.033447265625,
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0.038818359375,
-0.00958251953125,
0.005523681640625,
-0.0771484375,
0.08056640625,
0.0172119140625,
0.05615234375,
-0.006378173828125,
-0.0791015625,
0.033935546875,
0.09619140625,
0... | 40,900 | 40900 | |
Please find this inverse function
October 22nd 2008, 11:46 AM #1
Hi all,
could anybody find inverse function to this function:
$<br /> f(x) = \frac{2x}{1 - x^2}<br />$
Please write here the whole solution.
Thanks in advance.
A few have looked at this, but no takers. Let's see if I can get t... | 4 | [
-0.06396484375,
-0.041259765625,
0.01953125,
0.0517578125,
-0.0025634765625,
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0.052490234375,
-0.015625,
-0.0023956298828125,
-0.007232666015625,
-0.0164794921875,
0.01507568359375,
-0.01495361328125,
-0.06201171875,
0.06787109375,
-0.013671875,
-0.... | 40,901 | 40901 | |
Prove using induction (2)
August 13th 2011, 12:15 PM #1
Prove using induction (2)
Define a function $\mu$ on the set of non-negative integers as follows. Let $\mu(1)=1$, and let $\mu(n)=0$ if n > 1 and n is divisible by the square of an integer a > 1. Otherwise, if $n=
p_1p_2...p_k$, where the $p_i$ are all d... | 5 | [
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0.0390625,
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-0.006011962890625,
-0.0908203125,
-0.01153564453125,
0.03515625,
0.00347900... | 40,902 | 40902 | |
Math Induction
April 14th 2007, 08:02 PM #1
Junior Member
Joined
Mar 2007
Posts
34
Math Induction
Use to math induction prove:
F1^2 + F2^2 + … + Fn^2 = FnFn+1
Please help. Im stuck at the inductive step >.<
This is fairly standard in discrete mathematics courses for the Fibonacci sequ... | 4 | [
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0.00154876708984375,
0.08544921875,
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-0.0830078... | 40,903 | 40903 | |
Math Forum Discussions
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Topic: Onto [0,1]
Replies: 40 Last Post: Apr 29, 2013 10:... | 5 | [
0.0042724609375,
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-0... | 40,904 | 40904 | |
Calculate Backyard Aquaponic and Aquaculture Pipe Flows - Earthan Group - Paul Van der Werf
Following the short article When Your Flow Rate Goes Wrong some members and readers have asked for more detail on how to work out which pipe size is suitable for them to use in their backyard
aquaculture an aquaponic systems. T... | 5 | [
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0.078125,
-0.052978515625,
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0.044189453125,
-0.068359375,
0.03759765625,
-0.0947265625,
0.08984375,
-0.0... | 40,905 | 40905 | |
Derived functors vs universal delta functors
up vote 8 down vote favorite
10
I would like to understand the relationship between the derived category definition of a right derived functor Rf (which involves an initial natural transformation n: Qf → (Rf)Q, where Q is the map
to the derived category) and the "universal ... | 4 | [
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0.058349609375,
-0.00848388671875,
-0.018554687... | 40,906 | 40906 | |
Geodesic metrics that admit dilatation at each point
up vote 13 down vote favorite
4
Consider the class of geodesic metrics $g$ on manifolds, that have the following property: for each point $x$ there exists a neighbourhood $U_x$ and a smooth vector field $v_x$ in $U_x$ that vanishes
at $x$ and whose flow (for small t... | 4 | [
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Products of Integers (Even or Odd)
Associated Topics || Dr. Math Home || Search Dr. Math
Products of Integers (Even or Odd)
... | 4 | [
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0.0458984375... | 40,908 | 40908 | |
Two In the Shop
Suppose we have 10 units in service, each with an MTBF (Mean Time
Between Failure) of 2,000 hours. Each operates for 2 months per
year. When one fails it is returned to the maintenance shop for
repair, and spends 1 week there. What is the probability that
two units will be in the maintenance shop at... | 5 | [
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-0.0252685546875... | 40,909 | 40909 | |
quadratic equation - discrimination
Your expression for the discriminant can be re-arranged into $D = 4(a^2 - a(b+c) + (b^2 - bc + c^2))$. For unequal roots (ie. two distinct roots) you want $a^2 - a(b+c) + (b^2 - bc + c^2) eq 0$. NB
(an acronym for the latin phrase nota bene which translates as note well, that is, wha... | 4 | [
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0.0458984375,
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-0.049072265625,
0.0225830078125,
0.02966... | 40,910 | 40910 | |
Math Forum Discussions
Math Forum
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Discussions
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Views expressed in these public forums are not endorsed by Drexel University or The Math Forum.
Math Forum » Discussions » Policy and News » geometry.ann... | 4 | [
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0.04248046875,
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-0.08154296875,
0.00... | 40,911 | 40911 | |
Truncation and Taylor series
October 16th 2009, 01:04 PM #1
Junior Member
Joined
Oct 2009
Posts
31
Truncation and Taylor series
Hi all,
If I expand the function
$y(t_{n+1})$ about $y(t_n)$and get
$y(t_{n+1}) = y(t_n) + h y'(t_n) + h^2/2 y''(t_n) + ....$
what do I get if I expand the f... | 4 | [
-0.04736328125,
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0.053955078125,
0.00897216796875,
0.05908203125,
-0.0341796875,
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0.05712890625,
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0.0947265625,
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-0.0859375,
-0.1337890625,
-0.03857421875,
-0.037109375,
-0.08984375,
-0.01965332... | 40,912 | 40912 | |
How to solve this recurrence relation ?
it is only a recursive problem. 3P(n) = 1 - P(n-1) 3P(n-1) = 1 - P(n - 2) ... How to figure out P(n) = ?
But i want to figure out a p(n) = n 's function but not a recurrence sequence.
Hello, denniszeng! Quote: $3\!\cdot\!P(n) \:=\: 1-P(n-1)\qquad\text{Find }P(n)$ Let $P(n) \:=\... | 5 | [
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0.05517578125,
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0.0000972747802734375,
-0.0252685546875,
0.0157470703125,
-0.072265625,
-0.05810546875,
... | 40,913 | 40913 | |
Numerical solution of linear Schroedinger ODE with almost-normal Hamiltonian matrix
up vote 1 down vote favorite
1
I am calculating numerical solutions of time-dependent Schroedinger equation
$\frac{d\Psi}{dt} = - i H \Psi$
where $\Psi$ is an $N$-element complex vector and $H$ is an $N \times N$ complex matrix, whic... | 4 | [
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0.0380859375,
0.04931640625,
0.01... | 40,914 | 40914 | |
Maximal domain and range
April 12th 2010, 02:30 PM #1
Member
Joined
Nov 2009
Posts
75
Maximal domain and range
im very vERY confused..
first of all,can anyone confirm to me if 'maximal' domain and 'domain' are the same?
i am trying to find maximal domain & range of these on the real line:
... | 4 | [
0.01226806640625,
-0.07275390625,
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-0.09375,
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-0.0223388671875,
0.02978515625,
-0.08... | 40,915 | 40915 | |
Some questions about causal structure of space-time.
up vote 3 down vote favorite
1
• Let $(\hat{M},\hat{g})$ be the conformal compactification of a space-time $(M,g)$. Let $I^+$ be the conformal null infinity and $J^{-}(I^+)$ be its causal past. Then the spacetime will be called
"asymptotically strongly predic... | 5 | [
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-0.06982421... | 40,916 | 40916 | |
Measures of non-abelian-ness
up vote 18 down vote favorite
9
Let $G$ be a finite non-abelian group of $n$ elements. I would like a measure that intuitively captures the extent to which $G$ is non-commutative. One easy measure is a count of the non-commutative
products. For example, for $S_3$, 9 products are non-commut... | 4 | [
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0.0181884765625,
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0.0162353515625,
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-0.044189453125,
-0.040283203125,
-0.022216796875,
0.000537872314453125,
0... | 40,917 | 40917 | |
How about a massive catapult to replace the space shuttle
I recently saw a comment on a blog somewhere about putting satellites into space (I think it was from a post about a rocket that blew up). The poster suggested using a giant catapult to put things in
space instead of rockets. Maybe he or she was kidding, or mayb... | 5 | [
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0.07275390625,
-0.016357421875,
0.0712890625,
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0.0556640625,
0.037353515625,
0.004119873046875,
0.0361328125,
-0.00311279296875,
0.0888671875,
0.073730... | 40,918 | 40918 | |
Inequalities for eigenvalues of matrices
Journal of Inequalities and
Applications
This Provisional PDF corresponds to the article as it appeared upon acceptance. Fully formatted
PDF and full text (HTML) versions will be made available soon.
... | 5 | [
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0.06689453125,
0.06494140625,
-0.0... | 40,919 | 40919 | |
Maximal consistent sets are complete
March 25th 2010, 07:54 PM
Giraffro
Maximal consistent sets are complete
I'm stuck on a problem on the theory of structures and essentially boiled it down to this: If $\Gamma$ is a maximal consistent set of sentences ( $\forall \phi \in \text{Sent}(\mathcal{L}), \
Gamma \v... | 5 | [
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0.0079345703125,
0.09912109375,
-0.04101... | 40,920 | 40920 | |
Existence of zero cycles of degree one vs existence of rational points
up vote 16 down vote favorite
2
Let $k$ be a field (I'm mainly interested in the case where $k$ is a number field, however results for other fields would be interesting), and $X$ a smooth projective variety over $k$.
By a zero cycle on $X$ over $k... | 5 | [
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0.099609375,
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0.0419921875,
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0.05322265625,
-0.00787353515625,
0.059814453125,
0.01373291015625,
-0.056884765625,
-0.00695800781... | 40,921 | 40921 | |
Making MATLAB svd robust to transpose operation
up vote 2 down vote favorite
I'm playing with MATLAB's svd function to compute the svd of
[ 1 4 7 10
2 5 8 11
3 6 9 12 ]
When I type [U1, ~, ~] = svd(X), I get
U1 =
-0.5045 0.7608 0.4082
-0.5745 0.0571 -0.8165
-0.... | 4 | [
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-0.054931640625,
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-0.03759765625,
0.01483154296875,
-0.059326171875,
-0.068359375,
-0.047119140... | 40,922 | 40922 | |
square roots and negative infinity
October 25th 2009, 03:30 PM #1
Member
Joined
Sep 2009
Posts
149
square roots and negative infinity
problem:
Find the limit. (If you need to use -
I would explain what ive done in more detail, but i know im missing something due to x approaching neg. infinity, ... | 4 | [
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0.04345703125,
0.0537109375,
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0.07568359375,
0.02197265625,
0.035888671875,
0.04833984375,
-0.052001953125,
0.0186767578125,
0.0703125,
-0.0849609375,... | 40,923 | 40923 | |
Surface automorphisms and conformal automorphisms
up vote 5 down vote favorite
1
Given a closed orientable surface $S$ and a topological automorphism $\sigma$ of $S$, it is not in general possible to find a conformal structure $\Sigma$ on $S$ so that $\sigma$ is isotopic to a
conformal automorphism of the Riemann surf... | 4 | [
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-0.0703125,
-0.0208740234375,
0.0262451171875,
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0.021240234375,
-0.0296630859375,
-0.044189453125,
-0.10205078125,
-0.058... | 40,924 | 40924 | |
Archimedes' principle: worked examples
Archimedes' principle: worked examples
1. A ship of mass 1200 t floats in sea-water. What volume of sea-water does it displace?If the ship enters fresh water, what weight of cargo must be unloaded so that the same volume of water is
displaced as before? ( Density of fresh water... | 4 | [
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0.05615234375,
-0.0888671875,
-0.031494140625,
-0.09033203125,
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0.05224609375,
-0.1025390625,
-0.00921630859375,
-0.0301513671875,
0.062011718... | 40,925 | 40925 | |
The sum of certain consecutive odd numbers is 57^2 – 13^2. Find the numbers.
April 29th 2009, 06:52 PM #1
Newbie
Joined
Apr 2009
From
chennai,india
Posts
9
The sum of certain consecutive odd numbers is 57^2 – 13^2. Find the numbers.
Problem.
The sum of certain consecutive odd numbers is $57^2$– $... | 4 | [
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0.0615234375,
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-0.0279541015625,
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-0.059326171875,
-0.05810546875,
-0.04638671875,
-0.0654296875,
-0... | 40,926 | 40926 | |
On the integer factorization and Nullstellensatz linear algebra: Fighting monomials.
Previous post show the idea. The problem is that one need to find polynomials of high degree to get the number of coefficients equal to the number of monomials. Too many monomials have to be killed.
Here is another way to hunt. Shor’s... | 4 | [
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0.0517578125,
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0.019775390625,
0.0279541015625,
0.0201416015625,
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-0.050048828125,
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-0.003265380859375,
0.00946044921875,
-0.026123046875,
-0.030517578125,
0.10498046875,
-0.018432... | 40,927 | 40927 | |
Do semisimple algebraic groups always have faithful irreducible representations?
up vote 15 down vote favorite
5
For simplicity, I will be talking only about connected groups over an algebraically closed field of characteristic zero.
The basic theorem of affine algebraic groups is that they all admit faithful, finite... | 5 | [
-0.02587890625,
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0.060302734375,
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0.0234375,
-0.01953125,
-0.05419921875,
-0.0263671875,
0.07568359375,
-0.06... | 40,928 | 40928 | |
Cohomology groups of homogeneous spaces
up vote 4 down vote favorite
5
Is there a general method to calculate the cohomology groups of homogeneous spaces ($G/H$), such as $\frac{U(4)}{U(2)\times U(2)}$, $\frac{U(5)}{U(2)\times U(3)}$, $U(4)/U(2)$, etc. If yes, could you
give the references for the method? Can this be ... | 4 | [
-0.08154296875,
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0.0791015625,
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0... | 40,929 | 40929 | |
QM - Part 1 - Eigenvalues of the Hermitian Operator A are real
March 12th 2011, 03:18 AM
bugatti79
QM - Part 1 - Eigenvalues of the Hermitian Operator A are real
Hi FOlks,
Studying this theorem 'Eigenvalues of the Hermitian Operator A are real' from sakurai's Modern QM's
$\hat A | a' \rangle = a'| a' \... | 5 | [
-0.08056640625,
0.0004425048828125,
0.02392578125,
-0.057861328125,
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-0.06591796875,
0.0034332275390625,
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0.036376953125,
-0.047119140625,
0.0042724609375,
0.0306396484375,
-0.033935546875,
0... | 40,930 | 40930 | |
Martin's cone theorem and recursion theory
up vote 9 down vote favorite
1
Martin's remarkable cone theorem in the theory of determinacy says the following:
Suppose $A\subseteq \omega^\omega$ is Turing invariant and determined. If $\forall x\exists y(x\le_T y\& y\in A)$ then $A$ contains a cone.
Let me explain wh... | 4 | [
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0.0311279296875,
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0.02392578125,
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Real Analysis - Sequences #2
January 20th 2009, 01:21 PM #1
Member
Joined
Oct 2008
Posts
135
Real Analysis - Sequences #2
Hey, I have been having trouble ever since I took part 1 of this class. So, here is question 2:
Assume that (fn) converges uniformly to f on A and that each fn is uniformly conti... | 4 | [
-0.0150146484375,
-0.04541015625,
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0.07958984375,
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0.140625,
-0.0238037109375,
0.026611328125,
-0... | 40,932 | 40932 | |
Spectral radius of a proper subgraph
up vote 4 down vote favorite
1
I came across a Chinese reference in the paper "On the spectral radius of trees with fixed diameter" by Guo and Shao. The attribute the following to Q. Li, K.Q. Feng in: "On the largest eigenvalue of
graphs", Acta Math. Appl. Sinica 2 (1979) 167–175.
... | 5 | [
-0.03369140625,
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0.025390625,
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0.08740234375,
0.0419921875,
-... | 40,933 | 40933 | |
More Vector Questions
January 21st 2010, 03:07 PM #1
Super Member
Joined
Dec 2008
Posts
509
More Vector Questions
Hi
I need help on the following questions:
1)Given $a=i+2j+3k, b=2i-3j+2k$ and $c=i+j-k$, find the angle between b and c.
This is what i have done: $cos^{-1}\frac{2}{\sqrt17\sqrt1... | 4 | [
-0.0703125,
0.056396484375,
-0.04443359375,
-0.051025390625,
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0.0186767578125,
-0.039794921875,
0.095703125,
0.05908203125,
-0.0859375,
0.0205078125,
0.0013885498046875,
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0.006683349609375,
-0.0167236328125,
-0.005... | 40,934 | 40934 | |
Compound Interest Savings Account
January 31st 2009, 06:52 PM #1
Member
Joined
Jan 2009
From
Punjab, Pakistan
Posts
88
Hi All
I am new to this forum, so I hope you would not mind the links in this message as I needed to list them to explain my query.
I design, develop and host online graphin... | 5 | [
0.025390625,
0.0693359375,
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0.00177764892578125,
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0.05810546875,
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0.0888671875,
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0.06494140625,
0.05615234375,
0.0361328125,
-0.1103515625,
-0.0324707... | 40,935 | 40935 | |
series convegnce
January 12th 2009, 09:38 AM #1
Newbie
Joined
Jan 2009
Posts
9
series convegnce
Hi
How do I find limit of convegence of the series
a>1 ; n goes from 1 to infinity
sigma[n/(a^n)]
Thanks
${{\varphi }_{n}}=\frac{n}{{{a}^{n}}}\implies \sqrt[n]{{{\varphi }_{n}}}=\frac{... | 5 | [
-0.005340576171875,
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-0.0654296875,
0.012451171875,
-0... | 40,936 | 40936 | |
Non-Hölder continuous devil's staircases
up vote 7 down vote favorite
1
Let $f:[0,1]\to[0,1]$ be a devil's staircase in the usual sense. (That is, $f$ is continuous, non-decreasing, $f'=0$ on a set of full Lebesgue measure.) We also require the complement to the set
where $f'$ vanishes to have Hausdorff dimension zero... | 5 | [
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... | 40,937 | 40937 | |
Can a metric conformal to a Kahler metric be Kahler?
up vote 9 down vote favorite
2
Let $X$ be a non-compact complex manifold of dimension at least 2 equipped with a Kahler metric $\omega$. Take a smooth positive function $f : X \to \mathbb R$, and define a new hermitian metric on
$X$ by $\tilde \omega = f \omega$. If... | 5 | [
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0.033203125,
-0.1005859375,
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0.0177001953125,
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0.0439453125,
0.06494140625,
-0.05029296875,
-0.06396484375,
0.038574218... | 40,938 | 40938 | |
viewing the second fundamental form as a tensor
up vote 2 down vote favorite
1
Dear all,
Thank you for your time reading this post. I am a student in computer science so this viewpoint of the second fundamental form may be interesting to you.
I would like to understand the second fundamental form of an affine (or pr... | 4 | [
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0.0118408203125,
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0.056884765625,
-0.007415771484375,
... | 40,939 | 40939 | |
Which changes of metric fix all open balls of a metric space?
up vote 9 down vote favorite
4
In an earlier question, I was interested in counting the number of metric spaces on N points, where I considered two metric spaces to be the same if they had the same collection of open balls. Two
questions:
1. What are the ... | 5 | [
0.0106201171875,
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0.0126953125,
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-0.091796875,
0.047607421875,
0.00482177... | 40,940 | 40940 | |
Tetris-like falling sticky disks
up vote 34 down vote favorite
8
Suppose unit-radius disks fall vertically from $y=+\infty$, one by one, and create a random jumble of disks above the $x$-axis. When a falling disk hits another, it stops and sticks there. Otherwise,
if the disk center reaches $y=0$, the disk stops with ... | 4 | [
-0.057861328125,
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-0.0198974609375,
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0.052490234375,
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0.09375,
-0.0023040771484375,
-0.05517578125,
0.01446533203125,
-... | 40,941 | 40941 | |
ack
Data::SecsPack - pack and unpack numbers in accordance with SEMI E5-94
#####
# Subroutine interface
#
use Data::SecsPack qw(bytes2int config float2binary
ifloat2binary int2bytes
pack_float pack_int pack_num
str2float str2int
unpack... | 4 | [
0.0234375,
0.0693359375,
-0.1318359375,
-0.059326171875,
0.007232666015625,
-0.046875,
0.0299072265625,
0.058837890625,
-0.055908203125,
-0.00005507469177246094,
0.0771484375,
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-0.0277099609375,
0.0234375,
0.002593994140625,
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0.0615234375,
... | 40,942 | 40942 | |
Instantaneous rate of change of a sphere
September 23rd 2008, 07:48 PM #1
Junior Member
Joined
Sep 2008
Posts
48
Instantaneous rate of change of a sphere
Hi, I need help finding the final answer of this, I know how to do it, but i'm not sure what the final answer should be:
The volume, V, of a spher... | 4 | [
-0.0018463134765625,
0.035888671875,
-0.00982666015625,
-0.0341796875,
0.0595703125,
-0.060791015625,
-0.023681640625,
0.027587890625,
0.1015625,
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-0.06298828125,
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0.1142578125,
0.021728515625,
0.0028228759765625,
-0.0034637451171875,
0.023... | 40,943 | 40943 | |
[SciPy-user] error estimate in stats.linregress
josef.pktd@gmai... josef.pktd@gmai...
Tue Feb 24 10:06:15 CST 2009
On Tue, Feb 24, 2009 at 9:17 AM, Bruce Southey <bsouthey@gmail.com> wrote:
> josef.pktd@gmail.com wrote:
>> On Mon, Feb 23, 2009 at 4:45 PM, Bruce Southey <bsouthey@gmail.com> wrote:
>>
>>> josef.pktd@gm... | 4 | [
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0.0269775390625,
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0.0037841796875,
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0.03271484375,
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-0.01409912109375,
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-0.0179443359375,
-0.0169677734375,
-... | 40,944 | 40944 | |
Math Help
February 14th 2009, 01:10 PM #1
Newbie
Joined
Feb 2009
Posts
5
Span
Let W be the set of all (X1, X2, X3, X4, X5) in R5 which satisfy
2X1-X2+4/3X3-X4=0
X1+2/3X3-X5=0
9X1-3X2+6X3-3X4-3X5=0
Find a finite set of vectors which spans W
Does this mean I have to find the vectors s... | 5 | [
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0.01007080078125,
-0.03515625,
0.08544921875,
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-0.0791015625,
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0.00201416015625,
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0.041259765625,
-0.032470703125,
... | 40,945 | 40945 | |
solve variables in terms of variables
February 5th 2007, 06:01 PM
dazed&confuzed
solve variables in terms of variables
Help would be appreciated.
1.)
Solve this formula for the variable $\mu$:
z = $\frac{x-\mu}{\mu}$
2.)
Solve this formula for the variable R:
$\frac{E}{e}$ = $\fra... | 4 | [
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0.0301513671875,
0.044921875,
0.03173828125,
0.054443359375,
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0.049072265625,
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0.1162109375,
0.09033203125,
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0.057861328125,
0.1162109375,
-0.009033203125,
0.038818359375,
-0.041748046875,
0.0286865234375... | 40,946 | 40946 | |
Sections measure zero imply set is measure zero?
up vote 4 down vote favorite
4
I have a subset $B\subset\mathbb{R}^n\times\mathbb{R}^m$ that I want to show has measure zero. I know that the sections $B^x = \{y : (x,y)\in B\}$ all have measure zero. I do not know if $B$ is
measurable. Is this enough to conclude that $... | 5 | [
0.04833984375,
-0.0703125,
-0.057861328125,
-0.005767822265625,
0.0419921875,
0.0400390625,
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0.04833984375,
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0.08544921875,
0.0341796875,
0.043212890625,
0.0810546875,
-0.0258... | 40,947 | 40947 | |
Finding the Difference of the Cubes of Two Numbers
Date: 9/29/95 at 21:57:3
From: Anonymous
Subject: Solve for x^3 - y^3
Here's the problem :
The difference of two numbers is 1.
The product of the two numbers is also 1.
What is the difference of the cubes of the numbers?
Date: 9/30/95 at 1:52:37
From: Doctor Andr... | 4 | [
-0.00921630859375,
0.04150390625,
-0.07763671875,
0.044189453125,
-0.046630859375,
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0.0693359375,
0.1044921875,
-0.00726318359375,
-0.07421875,
0.022216796875,... | 40,948 | 40948 | |
Fermi estimate challenge
I'll invite you to help me with this challenge, namely by providing the challenges. Enrico Fermi was famous for being able to estimate physical quantities even in situations where he did not (and,
possibly, nobody) knew what the actual answer was. This is enormously helpful in science. One of t... | 4 | [
-0.02685546875,
0.078125,
0.036865234375,
0.1171875,
-0.0869140625,
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0.09716796875,
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0.0186767578125,
-0.1201171875,
-0.07177734375,
0.0693359375,
0.01080322265625,
... | 40,949 | 40949 | |
solving Equations with fractions
I am having a problem solving is 4 a solution to 1/2 (y-2)+2= 3/8 (3y-4) not sure where to begin.
Maybe expand these brackets and group some like terms to solve. Here's a kick start... $\frac{1}{2}(y-2)+2 = \frac{3}{8}(3y-4)$ $\frac{y}{2}-1+2 = \frac{9y}{8}-\frac{12}{8}$ $\frac{y}{2}+1... | 4 | [
-0.05908203125,
-0.01385498046875,
0.01458740234375,
0.0038604736328125,
0.035888671875,
-0.01611328125,
-0.1298828125,
0.0322265625,
0.0233154296875,
0.0179443359375,
0.033447265625,
-0.03662109375,
-0.01220703125,
0.061279296875,
0.0152587890625,
0.06787109375,
-0.01190185546875,
... | 40,950 | 40950 | |
Finding and Working with Ratios
Date: 12/26/2001 at 13:16:54
From: Hima Mehta
Subject: Ratios and proportions
1. What is the ratio of the circumference of a circle to its radius?
2. A snail can move i inches in m minutes. At this rate, how many
feet can it move in h hours?
Date: 12/26/2001 at 16:50:47
From: Do... | 4 | [
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0.0947265625,
-0.027587890625,
0.0654296875,
0.01953125,
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0.01556396484375,
-0.0111083984375,
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0.03662109375,
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0.04736328125,
0.10791015625,
0.013671875,
-0.01019287109375,
-0.0218505859375,
0.119140625,
... | 40,951 | 40951 | |
when tensor complex resolves S/I+J?
up vote -1 down vote favorite
Assume that $I\subset k[x_1,\ldots,x_n]$ and $J\subset k[y_1,\ldots,y_m]$ are monomial ideals in different rings, and the minimal free resolution of $S/I$ and $S/J$, say $F_\cdot$ and $G_\cdot$, are
both linear. I believe that $F\otimes G$ is a minimal... | 4 | [
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0.00860595703125,
0.015869140625,
-0.045654296875,
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0.08251953125,
0.004241943359375,
0... | 40,952 | 40952 | |
Backtracking explained
Backtracking is the programmer's swiss army knife: Most problems where you can't find another solution for are solved by backtracking.
Therefore I want to describe how to do backtracking using simple examples.
A (only little) more advanced example is solving Sudokus using backtracking as imple... | 5 | [
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0.055908203125,
-0.072265625,
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0.0341796875,
0.03271484375,
0.05224... | 40,953 | 40953 | |
Row Equivalence
Row Equivalence
Row Equivalence
Two ~m # ~n matrices A and B are said to be #{~{row equivalent}} if B can be obtained from a by a finite sequence of three types of #{~{elementary row operations}}:
1. multiply all elements of a row by a scalar
2. interchange a pair of rows
3. add a scalar multiple... | 4 | [
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0.0225830078125,
0.01031494140625,
0.078125,
0.01068115234375,
0.05859375,
-0.04... | 40,954 | 40954 | |
Need help with the algebra in an induction proof
February 23rd 2010, 11:41 PM
morbius27
Need help with the algebra in an induction proof
Hi, I've been working on this problem for quite a while now and I just can't seem to get the algebra working for it. Any help is appreciated.
Determine the exact set of na... | 4 | [
-0.044677734375,
0.0322265625,
0.050537109375,
0.080078125,
0.038330078125,
-0.033203125,
-0.0673828125,
-0.0003223419189453125,
-0.00072479248046875,
0.0240478515625,
-0.158203125,
-0.02001953125,
0.0272216796875,
-0.03564453125,
-0.023193359375,
0.0517578125,
-0.05224609375,
0.02... | 40,955 | 40955 | |
Math Forum Discussions
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Topic: Building an Equation to find (Maximum Y) ie Highes... | 4 | [
-0.0693359375,
-0.08447265625,
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-0.046875,
0.0693359375,
-0.0115356445... | 40,956 | 40956 | |
Proving Convergence
May 5th 2008, 03:07 AM
ah-bee
Proving Convergence
Let (
an) be a sequence which converges to 0. Use the definition of a convergent sequence to prove that the sequence (an^2) to 0.
Definition: There exists an L that is Real s.t. for every E>0 there exists N that is a positive integer... | 5 | [
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-0.0517... | 40,957 | 40957 | |
entire functions of one complex variable with prescribed value and order.
up vote 3 down vote favorite
In the complex plane, say $a_n \rightarrow \infty$ and $d_n$ and $A_n$ are arbitrary complex numbers. can we find an entire function with $f(a_n)=A_n$ with order $d_n$? (here "order" means $f(z)-A_n$
has a zero with ... | 5 | [
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0.003372192... | 40,958 | 40958 | |
What is the Dunford Integral and why is it useful?
up vote 5 down vote favorite
2
Wikipedia http://en.wikipedia.org/wiki/Pettis_integral defines the Pettis Integral for Banach space valued functions wrt to some measure space by duality.
It calls the Pettis & Bochner integral the weak & strong integral respectively, w... | 4 | [
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0.112304687... | 40,959 | 40959 | |
Math Forum Discussions
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Topic: NonlinearModelFit Problem
Replies: 3 Last Post: Ja... | 5 | [
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0.0189208984375,
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0.00... | 40,960 | 40960 | |
Functional Analysis Proof: complete metric space
April 10th 2013, 07:53 PM #1
Newbie
Joined
Apr 2013
From
Cambridge, MA
Posts
3
Functional Analysis Proof: complete metric space
Define the space
β1([a,b])
as the space of functions
f:[a,b]↦R
which are everywhere differentiable and w... | 5 | [
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-0.0505371093... | 40,961 | 40961 | |
Area between Polar Curves
November 24th 2008, 10:37 PM #1
Member
Joined
Sep 2008
From
California
Posts
101
Hello, I have the problem: Find the area of the region outside
So I need to figure out the limits, so I set the r's equal and got $\sin \theta =\frac{1}{9}$ So I have a lower limit of .11134 ... | 5 | [
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-0.01092529296875,... | 40,962 | 40962 | |
Stack
CS212: Data Structures and
Algorithms
Lecture # 2
Stack
Outline
Introduction to Data Structures
Stack
Concepts
Common examples
Common operations
Array implementation
Applications of stack
Reversing the string
Ba... | 5 | [
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0... | 40,963 | 40963 | |
Optimal 8-vertex isoperimetric polyhedron?
up vote 8 down vote favorite
3
I know from Marcel Berger's Geometry Revealed: A Jacob's Ladder to Modern Higher Geometry (p.531) that it is not yet established which polyhedron in $\mathbb{R}^3$ on 8 vertices achieves the optimal
isoperimetric ratio $A^3/V^2$, where $A$ is th... | 5 | [
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Montgomery's conjecture and lower bound on certain Fourier transform.
up vote 7 down vote favorite
2
Recently I have come across the following question, while meditating about Matt Young's answer to this question of mine, explaining the heuristic (or at least, one possible heuristic) behind
Montgomery's conjecture on ... | 4 | [
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Newest 'integration na.numerical-analysis' Questions
The $n$th Gauss-Laguerre quadrature aims to approximate integral $$\int_{\mathbb{R}_+} f(x) \exp(-x)$$ by the sum $$\sum_{i=1}^n f(x_i) w_i$$ where $x_1,...,x_n$ are the roots of the $n$th Laguerre
...
I'd like to have an algorithm for a numerical calculatio... | 4 | [
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-0.03125,
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0.0361328125,
0.03393554... | 40,966 | 40966 | |
Math Help
prove that if a+ b/a - 1/b is an integer then it is a perfect square for integers a, b.
By setting a=-1, b=1 you can see the statement does not hold. But let's try to fix it: "if a+ b/a - 1/b is an integer then it is a perfect square for positive integers a, b." So let $a+\frac{b}{a}-\
frac{1}{b} = a+\frac{... | 5 | [
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0.03515625,
0.025390625,
-0.00364... | 40,967 | 40967 | |
help me understand a line in an "ATA is positive, semi-definite" proof
April 17th 2012, 10:03 PM
psholder
help me understand a line in an "ATA is positive, semi-definite" proof
I am looking at a proof for why A^TA is positive semi-definite when A is nxn and it has this line.
v^TAA^Tv = A^Tv • A^Tv ≥ 0.
... | 4 | [
-0.035888671875,
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0.0322265625,
0.00494384765625,
0.04296875,
0.035400390625,
-0.113769... | 40,968 | 40968 | |
Orbifold fundamental group in terms of loops?
up vote 8 down vote favorite
5
In chapter 13 in his notes on 3-manifolds, Thurston defines the orbifold fundamental group to be the group of deck transformations of the universal cover of the orbifold. He also makes a statement
"Later we shall interpret $\pi_1(O)$ in terms... | 4 | [
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0.0... | 40,969 | 40969 | |
Universal and efficient compressed sensing by spread spectrum and application to realistic Fourier imaging techniques
Abstract
We advocate a compressed sensing strategy that consists of multiplying the signal of interest by a wide bandwidth modulation before projection onto randomly selected vectors of an orthonormal ... | 4 | [
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sum to product formula
April 17th 2008, 03:27 PM
algebra2
sum to product formula
use sum to product formula:
[sinx+siny=2sin(x+y)cos(x-y)] to solve [0,2pi).
sin3x + sinx = 0
-----------------------
this is what i did and got stuck on:
1. sin(3x+x)
2. (2sin(3x+x)/2)cos(3x-x)/2
3. ... | 4 | [
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0.0390625,
... | 40,971 | 40971 | |
Trig Identity
November 22nd 2013, 04:02 PM #1
Trig Identity
Very tough... I am thinking now of working with the right side and doing :
cot(x/2) * cot(2x)/cot(2x)
= cot^2x/cot2x // Is this true?
because I have no idea what to do when I am given some thing like (x/2)
Any hints are really apprecia... | 4 | [
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... | 40,972 | 40972 | |
Maxima/minima problem
January 20th 2006, 05:50 AM #1
Maxima/minima problem
I have a max/min prob I have been trying to nut out and just can't seem to see it. Any help woudl be very appreciated.
thanks jacs
jacs
I have a max/min prob I have been trying to nut out and just can't seem to see it. Any he... | 5 | [
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0.0218505859375,
-0.002548... | 40,973 | 40973 | |
rtybase
This is the second post dedicated to the problems set posted on "Math, Math Education, Math Culture" LinkedIn group. Here is the original LinkedId discussion, again ... if you happen to have a
LinkedIn account. Here is the problem:
Prove that the sequence a[1]=1, a[2]=11, a[3]=111, a[4]=1111,... contains an in... | 5 | [
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String diagrams for (weak) monoidal categories
up vote 7 down vote favorite
1
Hi,
In a strict monoidal category, where the associator, left and right unitor are identity morphisms we have the following relations between (string) diagrams:
where $i_x$ and $e_x$ are the unit and counit isomorphisms.
For the first rel... | 4 | [
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0.0032... | 40,975 | 40975 | |
How to: Create a Custom Solver Report using the Solver APIs
If you are using a third-party solver, you can use the Solver reporting APIs to report data about custom properties. The following linear programming example demonstrates how to create a sensitivity
and infeasibility report at the solver level. In this exampl... | 5 | [
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0.01153564453125,
0.0771484375,
0.0070495605468... | 40,976 | 40976 | |
Wikipedia's definition of 'locally free sheaf'
up vote 11 down vote favorite
7
Let $R$ be a, say, noetherian ring and $M$ an $R$-module. The Wikipedia article on 'locally free sheaf' tells me that the following two statements are equivalent:
1. The module $M$ is locally free (Edit: this means there is an open cover ... | 4 | [
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0.04... | 40,977 | 40977 | |
Lecture 8a. A primer on simplicial complexes and collapsibility
Lecture 8a. A primer on simplicial complexes and collapsibility
Before we can apply more advanced fixed point theorems to the Evasiveness Conjecture, we need a little background on simplicial complexes, and everything starts with simplices.
Simplices
I... | 4 | [
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0.012451171875... | 40,978 | 40978 | |
Checking a solution on congruence equation
January 18th 2010, 11:17 AM #1
Junior Member
Joined
Oct 2009
Posts
66
Allright one more i did the problem just wanted to make sure i got all the steps right. The problem was 57x + 7 (congruent to) 78mod53.
For my solution ill just use equal as congruence.
... | 4 | [
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The Reference Frame
Optical rotation in magnetic field and axions
Sean Carroll mentions three experiments:
• B-meson oscillations that we discussed here
• MINOS (neutrinos) that we described here
• Rotating light in a magnetic field
We have not yet talked about the last one even though the
preprint
written b... | 4 | [
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... | 40,980 | 40980 | |
Question about orthogonal trajectories
Find the orthogonal trajectories of the family of ellipses (x^2/ a^2)+(y^2)=k^2 where a is a given constant.
For orthogonal trajectories, the tangents to the two respective curve are orthogonal. Slope of the tangent for your ellipse is given by $<br /> \frac{dy}{dx} = - \frac{x}{... | 4 | [
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... | 40,981 | 40981 | |
How many ways can the number 50 be witten as the sum of 10 non-negative, even number?
April 7th 2009, 04:28 PM #1
Newbie
Joined
Apr 2009
Posts
15
Hi,
Please help me to find out: in how many ways the number 50 can be witten as the sum of 10 non-negative, even numbers?
Thanks alot.
Hello, gra... | 5 | [
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-0.... | 40,982 | 40982 | |
Aliasing
Talk0
34,135pages on
this wiki
Assessment | Biopsychology | Comparative | Cognitive | Developmental | Language | Individual differences | Personality | Philosophy | Social |
Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology |
Cognitive Psychology: Attention ... | 4 | [
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-0.031494140625,
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... | 40,983 | 40983 | |
When are there enough projective sheaves on a space X?
up vote 25 down vote favorite
14
This question is being asked on behalf of a colleague of mine.
Let X be a topological space. It is well known that the abelian category of sheaves on X has enough injectives: that is, every sheaf can be monomorphically mapped to a... | 4 | [
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0.09814453125,
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0.033447265625,... | 40,984 | 40984 | |
Riemann-Roch Theorem for Curves
Today we’re going after one of the most famous theorems of algebraic geometry: the Riemann-Roch Theorem. For it, we depart the world of general schemes and return to varieties. And not just any
varieties, but nonsingular complete curves.
The reason we need nonsingularity is because we’... | 5 | [
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... | 40,985 | 40985 | |
linear order in a group of functions
up vote 6 down vote favorite
2
Let $A$ be the smallest set of the following functions on the positive reals:
• The identity function is in $A$,
• for a function $f\in A$ also the inverse $f^{-1}$ is in $A$,
• for two functions $f,g\in A$ also the sum $f+g$, the product $f\cd... | 5 | [
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0.00723266... | 40,986 | 40986 | |
Gromov's Hyperbolicity and Positive Cheeger Constant in Planar Graphs
up vote 12 down vote favorite
8
It is known that for metric graphs the concepts of Gromov's hyperbolicity and strictly positive Cheeger constant are related. Let us first recall the definition of the Cheeger constant. Let $G$ be a
graph with vertex ... | 5 | [
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0.058837890... | 40,987 | 40987 | |
Double integral with polar coordinates
April 19th 2011, 06:59 PM #1
Member
Joined
Dec 2010
Posts
92
Double integral with polar coordinates
Evaluate the given integral by changing to polar coordinates.
...where D is the region bounded by the semicircle y-axis.
----
I do all my scrap work ... | 5 | [
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-0.040283203125,
... | 40,988 | 40988 | |
Math Help
July 15th 2007, 04:10 PM #1
Newbie
Joined
Jul 2007
Posts
6
Please someone help. I have summer school and I got a Take-Home Quiz. My teacher knows about the whole, google or yahoo the answer thing, so he does not care. Anyways one of the questions is
this: Write an equation of a parabola wit... | 4 | [
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0.04150390625,
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0.134765625,
-0.0140380859375,
-0.048... | 40,989 | 40989 | |
number of divisors
May 15th 2008, 03:58 PM #1
Newbie
Joined
May 2008
Posts
10
number of divisors
7a) How many different sums of money can be made from a 2$ bill, a 5$ bill and a 10$ bill
b) How many different sums of money can be made from the bills in a as well as one more 10$ bill
c) Why does t... | 4 | [
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-0.064453125,
-0.03955078125,... | 40,990 | 40990 | |
Math Help
March 6th 2009, 12:35 PM #1
Member
Joined
Nov 2006
Posts
142
PDE
Can someone help me solve this PDE:
ut = uxx - (B^2)u, 0 < x < L, t > 0
u(0,t) = U1, u(L,t) = U2, u(x,0) = f(x)
I will assume that U1 and U2 are constants. First you need to move them to zero. So let $u = v + ax + b... | 5 | [
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0.0018768310546875,
-0.0341796875,
0.00041961669921875,
0.060302734375,
-0.06591796... | 40,991 | 40991 | |
Is the following function decreasing on $(0,1)$?
up vote 18 down vote favorite
3
Hi,
I asked some time ago the following question on math.stackexchange, but I ask it here too since it remains unanswered.
The question concerns a function I encountered during research :
$$f(k):= k K(k) \sinh \left(\frac{\pi}{2} \frac... | 5 | [
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-0.... | 40,992 | 40992 | |
Solving a PDE ???
August 26th 2009, 01:23 PM
spearfish
Solving a PDE ???
Hey all,
I am trying to determine how many solns. the PDE Ut = Uxx has. However, I have no idea how to solve this PDE.
Unlike ODE's which you are given a fairly "standard" y and x variable equation, PDE's just lose me from the beg... | 5 | [
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-0.130859375,... | 40,993 | 40993 | |
Least Prime Factors: found a counting formula for a given range -- what is the standard approach?
up vote 4 down vote favorite
1
Hi Everyone,
I am a math amateur who for the past year has been working on better understanding Bertrand's Postulate, the Ramanujan Primes, and the recent expansion of Bertrand's Postulate ... | 4 | [
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0.024658203125,
-... | 40,994 | 40994 | |
Math Forum Discussions - An experiment . . . at random in intra-Permutations
Date: Mar 2, 2013 1:36 PM
Author: Luis A. Afonso
Subject: An experiment . . . at random in intra-Permutations
. . . at random
0__Preliminary
I did show that the set of modified means of a sample represents quite well its mean; its popula... | 4 | [
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0.0108642578125,
0.07861328125,
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0.126953125,
0.0732421875,
-0.0947265625,
-0.11572265625,
0.01165771484375,
0.12890625,
0.0524902343... | 40,995 | 40995 | |
Perfect Numbers
Date: 11/10/97 at 12:57:26
From: Juan Maria Moreno
Subject: Perfect numbers
I have found that the sums of the digits of perfect numbers greater
than 6 always equal 1.
28 2+8 = 10 = 1
496 4+9+6 = 19 = 10 = 1
33,550,336 3+3+5+5+0+3+3+6 = 28 = 10 = 1
Do th... | 5 | [
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0.00166320800781... | 40,996 | 40996 | |
Why a non-simple geodesic in a Y-piece is NOT homotopic to a common perpendicular to the geodesic boundaries ?
up vote 2 down vote favorite
This is a basic question, still I dare to ask :
Let Y be the Y-piece with geodesic boundaries A,B, C and ( if possible ) c the non simple geodesic from A to B intersecting itself... | 5 | [
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-0.05273... | 40,997 | 40997 | |
Sum of the Angles in a Star
Date: 09/21/1999 at 11:10:35
From: BonnaIII@aol.com
Subject: Problem
Please help me out with this problem I have.
Problem: Find the sum of the measures of the five acute angles that
make up a star.
Sincerely,
Manuel
Date: 09/21/1999 at 12:55:52
From: Doctor Peterson
Subject: Re: Probl... | 4 | [
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-0.07470703125,... | 40,998 | 40998 | |
Vectors
• Recall that “vectors” are arrows that
represent a vector quantity (magnitude and
direction).
– The length of the arrow represents the
magnitude of a measurement
– The direction of the arrow within a coordinate
system represents the... | 4 | [
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0.... | 40,999 | 40999 |