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int64
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742k
6.091. $\left\{\begin{array}{l}(x-y) \cdot x y=30 \\ (x+y) \cdot x y=120\end{array}\right.$
## Solution. After dividing the second equation of the system by the first, we get $\frac{(x+y) x y}{(x-y) x y}=\frac{120}{30}, y=\frac{3}{5} x$. From the first equation of the system, we find $\left(x-\frac{3}{5} x\right) x \cdot \frac{3}{5} x=30, x^{3}=5^{3}$, from which $x=5$; then $y=3$. Answer: $(5 ; 3)$
(5;3)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,748
6.093. $\left\{\begin{array}{l}v-u=1, \\ w-v=1, \\ (u-1)^{3}+(v-2)^{3}+(w-3)^{3}=3 .\end{array}\right.$
## Solution. From the first equation of the system, we find $y=1+u$. Substituting this value of $v$ into the second and third equations of the system, we have $$ \begin{aligned} & \left\{\begin{array} { l } { w - ( 1 + u ) = 1 , } \\ { ( u - 1 ) ^ { 3 } + ( 1 + u - 2 ) ^ { 3 } + ( w - 3 ) ^ { 3 } = 3 } \end{array} \...
(2;3;4)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,749
6.094. $\left\{\begin{array}{l}\frac{x+y}{x-y}+\frac{x-y}{x+y}=\frac{13}{6} \\ x y=5 .\end{array}\right.$
## Solution. Domain of definition: $x \neq \pm y$. Transforming the first equation of the system, we get $$ 6(x+y)^{2}+6(x-y)^{2}=13(x-y)(x+y) \Leftrightarrow x^{2}=25 y^{2} $$ from which $x_{1}=-5 y, x_{2}=5 y$. From the second equation of the system, we find $y^{2}=-1$ (not suitable) or $y^{2}=1$, from which $y...
(5;1),(-5;-1)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,750
6.095. $\left\{\begin{array}{l}3 x+2 y+2 z=13, \\ 2 x+3 y+2 z=14, \\ 2 x+2 y+3 z=15 .\end{array}\right.$
## Solution. By adding all three equations, we get $7(x+y+z)=42$, from which $x+y+z=6$. Now we will sequentially subtract this equation from each equation in the system: $$ \begin{aligned} & \left\{\begin{array}{l} 3 x+2 y+2 z=13, \\ x+y+z=6 \end{array} \Leftrightarrow x=1 ;\left\{\begin{array}{l} 2 x+3 y+2 z=14 \\ x...
(1;2;3)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,751
6.096. $\left\{\begin{array}{l}x^{2} y^{3}=16 \\ x^{3} y^{2}=2\end{array}\right.$
## Solution. Dividing the first equation of the system by the second, we get $\frac{y}{x}=8, y=8 x$. From the second equation of the system, we have $x^{3} \cdot 64 x^{2}=2, x^{5}=\frac{1}{32}$, from which $x=\frac{1}{2};$ then $y=4$. Answer: $\left(\frac{1}{2} ; 4\right)$
(\frac{1}{2};4)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,752
6.097. $\left\{\begin{array}{l}x+2 y+3 z=3, \\ 3 x+y+2 z=7, \\ 2 x+3 y+z=2 .\end{array}\right.$
## Solution. We will transform the system using the Gaussian method, i.e., subtract the first equation, multiplied by the corresponding number, from the second and third equations. $$ \begin{aligned} & \left\{\begin{array} { l } { x + 2 y + 3 z = 3 , } \\ { 3 x + y + 2 z = 7 , } \\ { 2 x + 3 y + z = 2 } \end{array} ...
(2,-1,1)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,753
6.098. $\left\{\begin{array}{l}x^{3}+y^{3}=7 \\ x y(x+y)=-2\end{array}\right.$
Solution. Rewrite the system of equations as $$ \left\{\begin{array} { l } { ( x + y ) ( x ^ { 2 } - x y + y ^ { 2 } ) = 7 , } \\ { x y ( x + y ) = - 2 } \end{array} \Leftrightarrow \left\{\begin{array}{l} (x+y)\left((x+y)^{2}-3 x y\right)=7 \\ x y(x+y)=-2 \end{array}\right.\right. $$ Let $\left\{\begin{array}{l}x+...
(2,-1),(-1,2)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,754
6.099. $\left\{\begin{array}{l}x^{2}+x y+y^{2}=91 \\ x+\sqrt{x y}+y=13\end{array}\right.$ Translate the above text into English, please retain the original text's line breaks and format, and output the translation result directly. 6.099. $\left\{\begin{array}{l}x^{2}+x y+y^{2}=91 \\ x+\sqrt{x y}+y=13\end{array}\right...
Solution. Domain of definition: $x y \geq 0$. Let $\left\{\begin{array}{l}\sqrt{x}=u \geq 0, \\ \sqrt{y}=v \geq 0,\end{array}\right.$ then $\left\{\begin{array}{l}x=u^{2}, \\ y=v^{2},\end{array}\left\{\begin{array}{l}x^{2}=u^{4}, \\ y^{2}=v^{4} .\end{array}\right.\right.$ With respect to $u$ and $v$, the system of e...
(1;9)(9;1)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,755
6.102. $\left\{\begin{array}{l}\sqrt{2 x-y+11}-\sqrt{3 x+y-9}=3 \\ \sqrt[4]{2 x-y+11}+\sqrt[4]{3 x+y-9}=3\end{array}\right.$ The system of equations is: \[ \left\{\begin{array}{l} \sqrt{2 x - y + 11} - \sqrt{3 x + y - 9} = 3 \\ \sqrt[4]{2 x - y + 11} + \sqrt[4]{3 x + y - 9} = 3 \end{array}\right. \]
Solution. Let $\left\{\begin{array}{l}\sqrt[4]{2 x-y+11}=u \geq 0, \\ \sqrt[4]{3 x+y-9}=v \geq 0 .\end{array}\right.$ With respect to $u$ and $v$, the system takes the form $$ \left\{\begin{array} { l } { u ^ { 2 } - v ^ { 2 } = 3 , } \\ { u + v = 3 } \end{array} \Leftrightarrow \left\{\begin{array} { l } { ( u - ...
(3;1)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,756
6.103. $\left\{\begin{array}{l}\sqrt{\frac{y}{x}}-2 \sqrt{\frac{x}{y}}=1, \\ \sqrt{5 x+y}+\sqrt{5 x-y}=4 .\end{array}\right.$ Translate the above text into English, please retain the original text's line breaks and format, and output the translation result directly. 6.103. $\left\{\begin{array}{l}\sqrt{\frac{y}{x}}-2...
Solution. Given: $\left\{\begin{array}{l}5 x+y \geq 0, \\ 5 x-y \geq 0, \\ \frac{y}{x}>0 .\end{array}\right.$ Let $\sqrt{\frac{y}{x}}=z>0$. Then $z-\frac{2}{z}=1$ or $z^{2}-z-2=0$, where $z \neq 0$. From this, $z_{1}=-1, z_{2}=2 ; z_{1}=-1<0$ is not suitable. Then $\sqrt{\frac{y}{x}}=2, \frac{y}{x}=4, y=4 x$. From t...
(1;4)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,757
6.106. $\left\{\begin{array}{l}u^{2}+v^{2}=u v+13 \\ u+v=\sqrt{u v}+3\end{array}\right.$ The system of equations is: \[ \left\{\begin{array}{l} u^{2}+v^{2}=u v+13 \\ u+v=\sqrt{u v}+3 \end{array}\right. \]
## Solution. Domain of definition: $u v \geq 0$. Let $\left\{\begin{array}{l}\sqrt{u}=x \geq 0, \\ \sqrt{v}=y \geq 0,\end{array}\left\{\begin{array}{l}u=x^{2}, \\ v=y^{2},\end{array}\left\{\begin{array}{l}u^{2}=x^{4}, \\ v^{2}=y^{4} .\end{array}\right.\right.\right.$ With respect to $x$ and $y$, we obtain the system...
(1;4),(4;1),(2-\sqrt{3};2+\sqrt{3}),(2+\sqrt{3};2-\sqrt{3})
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,758
6.108. $\left\{\begin{array}{l}3(2-\sqrt{x-y})^{-1}+10(2+\sqrt{x+y})^{-1}=5 . \\ 4(2-\sqrt{x-y})^{-1}-5(2+\sqrt{x+y})^{-1}=3 .\end{array}\right.$ ## Solution. Rewrite the system of equations as $\left\{\begin{array}{l}\frac{3}{2-\sqrt{x-y}}+\frac{10}{2+\sqrt{x+y}}=5 \\ \frac{4}{2-\sqrt{x-y}}-\frac{5}{2+\sqrt{x+y}}=3...
## Solution. Let $\left\{\begin{array}{l}\sqrt[3]{x}=u, \\ \sqrt[3]{y}=v,\end{array}\left\{\begin{array}{l}x=u^{3} \\ y=v^{3}\end{array}\right.\right.$, Relative to $u$ and $v$ the system takes the form $\left\{\begin{array}{l}u+v=4, \\ u^{3}+v^{3}=28\end{array} \Leftrightarrow\left\{\begin{array}{l}u+v=4, \\ (u+v)\l...
(1;27),(27;1)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,759
6.111. $\left\{\begin{array}{l}2(\sqrt{x}+\sqrt{y})=3 \sqrt{x y} \\ x+y=5\end{array}\right.$ The system of equations is: $\left\{\begin{array}{l}2(\sqrt{x}+\sqrt{y})=3 \sqrt{x y} \\ x+y=5\end{array}\right.$
## Solution. Domain of definition: $\left\{\begin{array}{l}x \geq 0, \\ y \geq 0 .\end{array}\right.$ Rewrite the system of equations as $\left\{\begin{array}{l}2(\sqrt{x}+\sqrt{y})=3 \sqrt{x y}, \\ (\sqrt{x}+\sqrt{y})^{2}-\sqrt{x y}=5\end{array}\right.$ and introduce the substitution $\left\{\begin{array}{l}\sqrt{x}...
(4;1)(1;4)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,760
6.112. $\left\{\begin{array}{l}\sqrt{x}+\sqrt{y}=10 \\ \sqrt[4]{x}+\sqrt[4]{y}=4\end{array}\right.$
Solution. Domain of definition: $\left\{\begin{array}{l}x \geq 0, \\ y \geq 0 .\end{array}\right.$ Let $\left\{\begin{array}{l}\sqrt[4]{x}=u \geq 0, \\ \sqrt[4]{y}=v \geq 0,\end{array}\left\{\begin{array}{l}\sqrt{x}=u^{2}, \\ \sqrt{y}=v^{2} .\end{array}\right.\right.$ Relative to $u$ and $v$, the system has the form ...
(1;81),(81;1)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,761
6.113. $\left\{\begin{array}{l}\sqrt{\frac{x+a}{y}}+\sqrt{\frac{y}{x+a}}=2, \\ x+y=x y+a .\end{array}\right.$
## Solution. Domain of definition: $\frac{x+a}{y}>0$. Let $\sqrt{\frac{x+a}{y}}=t$, where $t>0$. With respect to $t$, the equation takes the form $t+\frac{1}{t}=2, t^{2}-2 t+1=0, (t-1)^{2}=0$, from which $t=1$. Then $\sqrt{\frac{x+a}{y}}=1$, $\frac{x+a}{y}=1$, from which $y=x+a$. From the second equation, we get $$ ...
x_{1}=0,y_{1}=,x_{2}=2-,y_{2}=2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,762
6.114. $\left\{\begin{array}{l}y \sqrt{2 x}-x \sqrt{2 y}=6, \\ x y^{2}-x^{2} y=30\end{array}\right.$
## Solution. Domain of definition: $\left\{\begin{array}{l}x \geq 0, \\ y \geq 0 .\end{array}\right.$ Rewrite the first equation as $\sqrt{2}\left(\sqrt{x y^{2}}-\sqrt{x^{2} y}\right)=6$ and let $\sqrt{x y^{2}}=u, \sqrt{x^{2} y}=v$, where $u \geq 0, v \geq 0$. Then the system in terms of $u$ and $v$ becomes $$ \begi...
(\frac{1}{2};8)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,763
6.115. $\left\{\begin{array}{l}\sqrt[3]{x}+\sqrt[3]{y}=3 \\ \sqrt[3]{x^{2}}-\sqrt[3]{x y}+\sqrt[3]{y^{2}}=3\end{array}\right.$ The system of equations is: \[ \left\{\begin{array}{l} \sqrt[3]{x} + \sqrt[3]{y} = 3 \\ \sqrt[3]{x^{2}} - \sqrt[3]{x y} + \sqrt[3]{y^{2}} = 3 \end{array}\right. \]
Solution. Let $\left\{\begin{array}{l}\sqrt[3]{x}=u, \\ \sqrt[3]{y}=v,\end{array}\left\{\begin{array}{l}x=u^{3}, \\ y=v^{3}\end{array}\right.\right.$ With respect to $u$ and $v$, the system takes the form $$ \begin{aligned} & \left\{\begin{array} { l } { u + v = 3 , } \\ { u ^ { 2 } - u v + v ^ { 2 } = 3 } \end{arr...
(1;8),(8;1)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,764
6.116. $\left\{\begin{array}{l}\sqrt[4]{u}-\sqrt[4]{v}=1 \\ \sqrt{u}+\sqrt{v}=5\end{array}\right.$
Solution. Domain of definition: $\left\{\begin{array}{l}u \geq 0, \\ v \geq 0 .\end{array}\right.$ Let $\left\{\begin{array}{l}\sqrt[4]{u}=x \geq 0, \\ \sqrt[4]{v}=y \geq 0 .\end{array}\right.$ Relative to $x$ and $y$, the system takes the form $\left\{\begin{array}{l}x-y=1, \\ x^{2}+y^{2}=5\end{array} \Leftrightarr...
(16;1)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,765
6.118. $\left\{\begin{array}{l}\sqrt{\frac{x+y}{2}}+\sqrt{\frac{x-y}{3}}=14, \\ \sqrt{\frac{x+y}{8}}-\sqrt{\frac{x-y}{12}}=3 .\end{array}\right.$
## Solution. Domain of definition: $\left\{\begin{array}{l}x+y \geq 0, \\ x-y \geq 0 .\end{array}\right.$ Let $\left\{\begin{array}{l}\sqrt{\frac{x+y}{2}}=u, \\ \sqrt{\frac{x-y}{3}}=v,\end{array}\right.$ where $u \geq 0$ and $v \geq 0$. In terms of $u$ and $v$, the system becomes $\left\{\begin{array}{l}u+v=14, \\ \...
(124;76)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,766
6.119. $\left\{\begin{array}{l}\sqrt{x}-\sqrt{y}=0.5 \sqrt{x y} \\ x+y=5 .\end{array}\right.$
Solution. Domain of definition: $\left\{\begin{array}{l}x \geq 0 \\ y \geq 0 .\end{array}\right.$ Let $\left\{\begin{array}{l}\sqrt{x}=u, \\ \sqrt{y}=v,\end{array}\right.$ where $u \geq 0$ and $v \geq 0$. With respect to $u$ and $v$, the system takes the form $$ \begin{aligned} & \left\{\begin{array} { l } { u - v...
(4;1)
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,767
6.122. Form a second-degree equation, one of whose roots is equal to the sum, and the other to the product of the roots of the equation $a x^{2}+b x+c=0$.
Solution. Let $y^{2}+p y+q=0$ be the desired equation with roots $y_{1}=x_{1}+x_{2}$, $y_{2}=x_{1} \cdot x_{2}$. By Vieta's theorem, we have $$ \left\{\begin{array} { l } { y _ { 1 } = x _ { 1 } + x _ { 2 } = - \frac { b } { a } } \\ { y _ { 2 } = x _ { 1 } \cdot x _ { 2 } = \frac { c } { a } } \end{array} \quad \te...
^{2}y^{2}+(b-)y-=0
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,768
6.123. Form a quadratic equation whose roots are one unit greater than the roots of the equation $a x^{2}+b x+c=0$.
Solution. Let $y^{2}+p y+q=0$ be the desired equation with roots $y_{1}=x_{1}+1$, $y_{2}=x_{2}+1$. From the condition by Vieta's theorem $$ \begin{aligned} & \left\{\begin{array}{l} x_{1}+x_{2}=-\frac{b}{a}, \\ x_{1} \cdot x_{2}=\frac{c}{a}, \end{array}\right. \\ & \left\{\begin{array}{l} y_{1}+y_{2}=x_{1}+1+x_{2}+1=...
^{2}+(b-2)y+-b+=0
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,769
6.124. Determine the coefficients of the quadratic equation $x^{2}+p x+q=0$ so that its roots are equal to $p$ and $q$.
## Solution. By Vieta's theorem $\left\{\begin{array}{l}p+q=-p, \\ p q=q\end{array} \Leftrightarrow\left\{\begin{array}{l}2 p+q=0, \\ q(p-1)=0 .\end{array}\right.\right.$ From the second equation of the system, we have $q=0$ or $p-1=0$. Then $q_{1}=0, p_{1}=0 ; p_{2}=1, q_{2}=-2 p_{2}=-2$. Answer: $p_{1}=q_{1}=0 ; p...
p_{1}=q_{1}=0;p_{2}=1,q_{2}=-2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,770
6.125. Find the coefficients $A$ and $B$ of the equation $x^{2}+A x+B=0$, if it is known that the numbers $A$ and $B$ are its roots.
## Solution. By Vieta's theorem $$ \left\{\begin{array} { l } { A + B = - A , } \\ { A B = B } \end{array} \Leftrightarrow \left\{\begin{array} { l } { 2 A + B = 0 , } \\ { B ( A - 1 ) = 0 } \end{array} \Rightarrow \left\{\begin{array} { l } { A _ { 1 } = 0 , } \\ { B _ { 1 } = 0 } \end{array} \text { or } \left\{...
A_{1}=B_{1}=0;A_{2}=1,B_{2}=-2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,771
6.126. For what integer value of $k$ is one of the roots of the equation $4 x^{2}-(3 k+2) x+\left(k^{2}-1\right)=0$ three times smaller than the other?
Solution. From the condition, by Vieta's theorem, we have ![](https://cdn.mathpix.com/cropped/2024_05_22_fa9db84b44b98ec0a5c7g-338.jpg?height=326&width=956&top_left_y=913&top_left_x=152) where $k \in \mathbb{Z}$. From this, $37 k^{2}-36 k-76=0, k_{1}=2, k_{2}=-\frac{38}{37} \notin \mathbb{Z}$ (does not fit). Answer...
2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,772
6.127. For what integer value of $p$ do the equations $3 x^{2}-4 x+p-2=0$ and $x^{2}-2 p x+5=0$ have a common root? Find this root.
## Solution. Let $x_{1}$ be the common root, then $$ \begin{aligned} & \left\{\begin{array} { l } { 3 x _ { 1 } ^ { 2 } - 4 x _ { 1 } + p - 2 = 0 , } \\ { x _ { 1 } ^ { 2 } - 2 p x _ { 1 } + 5 = 0 } \end{array} \Leftrightarrow \left\{\begin{array}{l} 3 x_{1}^{2}-4 x_{1}+p-2=0, \\ 3 x_{1}^{2}-6 p x_{1}+15=0 \end{arra...
1,p=3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,773
6.128. Find all values of $a$ for which the sum of the roots of the equation $x^{2}-2 a(x-1)-1=0$ is equal to the sum of the squares of the roots.
## Solution. Given $x^{2}-2 a x+(2 a-1)=0$. By Vieta's theorem $\left\{\begin{array}{l}x_{1}+x_{2}=2 a, \\ x_{1} \cdot x_{2}=2 a-1 .\end{array}\right.$ Further, $$ x_{1}+x_{2}=x_{1}^{2}+x_{2}^{2}=\left(x_{1}+x_{2}\right)^{2}-2 x_{1} x_{2} \Leftrightarrow x_{1}+x_{2}=\left(x_{1}+x_{2}\right)^{2}-2 x_{1} x_{2} . $$ Us...
a_{1}=\frac{1}{2},a_{2}=1
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,774
6.129. For what value of $a$ do the equations $x^{2}+a x+8=0$ and $x^{2}+x+a=0$ have a common root?
## Solution. Let $x_{1}$ be the common root, then $$ \left\{\begin{array}{l} x_{1}^{2}+a x_{1}+8=0, \\ x_{1}^{2}+x_{1}+a=0 \end{array} \Rightarrow a x_{1}-x_{1}+8-a=0, x_{1}=\frac{a-8}{a-1}\right. $$ From the second equation of the system, we have $$ \begin{aligned} & \left(\frac{a-8}{a-1}\right)^{2}+\left(\frac{a-...
-6
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,775
6.130. In the equation $x^{2}-2 x+c=0$, determine the value of $c$ for which its roots $x_{1}$ and $x_{2}$ satisfy the condition $7 x_{2}-4 x_{1}=47$.
Solution. From the condition by Vieta's theorem we have $\left\{\begin{array}{l}x_{1}+x_{2}=2, \\ x_{1} \cdot x_{2}=c, \\ 7 x_{2}-4 x_{1}=47 .\end{array}\right.$ From here, $x_{2}=2-x_{1}$ and we obtain $$ \left\{\begin{array} { l } { x _ { 1 } ( 2 - x _ { 1 } ) = c } \\ { 7 ( 2 - x _ { 1 } ) - 4 x _ { 1 } = 4 7 } \...
-15
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,776
6.131. Without solving the equation $x^{2}-(2 a+1) x+a^{2}+2=0$, find the value of $a$ for which one of the roots is twice the other.
Solution. From the condition, by Vieta's theorem, we have $$ \left\{\begin{array} { l } { x _ { 1 } + x _ { 2 } = 2 a + 1 , } \\ { x _ { 1 } \cdot x _ { 2 } = a ^ { 2 } + 2 , } \\ { x _ { 2 } = 2 x _ { 1 } } \end{array} \Leftrightarrow \left\{\begin{array} { l } { 3 x _ { 1 } = 2 a + 1 , } \\ { 2 x _ { 1 } ^ { 2 } ...
4
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,777
6.132. For what value of $p$ is the ratio of the roots of the equation $x^{2}+p x-16=0$ equal to $-4$?
## Solution. By Vieta's theorem and the condition, we have the system $\left\{\begin{array}{l}x_{1}+x_{2}=-p, \\ x_{1} \cdot x_{2}=-16, \\ \frac{x_{2}}{x_{1}}=-4\end{array} \Leftrightarrow\left\{\begin{array}{l}x_{1}+x_{2}=-p, \\ x_{1} \cdot x_{2}=-16, \\ x_{2}=-4 x_{1}\end{array} \Rightarrow\left\{\begin{array}{l}x_...
p_{1,2}=\6
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,778
6.133. Without solving the equation $3 x^{2}-5 x-2=0$, find the sum of the cubes of its roots.
## Solution. By Vieta's theorem and the given condition, we have the system $$ \left\{\begin{array}{l} x_{1}+x_{2}=\frac{5}{3} \\ x_{1} \cdot x_{2}=-\frac{2}{3} \end{array}\right. $$ and $x_{1}^{3}+x_{2}^{3}=\left(x_{1}+x_{2}\right)\left(x_{1}^{2}-x_{1} x_{2}+x_{2}^{3}\right)=\left(x_{1}+x_{2}\right)\left(\left(x_{...
\frac{215}{27}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,779
6.134. For what integer value of $b$ do the equations $2 x^{2}+(3 b-1) x-3=0$ and $6 x^{2}-(2 b-3) x-1=0$ have a common root?
Solution. Let $x_{1}$ be the common root. Then $$ \begin{aligned} & \left\{\begin{array} { l } { 2 x _ { 1 } ^ { 2 } + ( 3 b - 1 ) x _ { 1 } - 3 = 0 , } \\ { 6 x _ { 1 } ^ { 2 } - ( 2 b - 3 ) x _ { 1 } - 1 = 0 } \end{array} \Leftrightarrow \left\{\begin{array}{l} 6 x^{2}+(9 b-3) x-9=0, \\ 6 x^{2}-(2 b-3) x_{1}-1=0 \...
2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,780
7.001. $\sqrt{25^{\frac{1}{\log _{6} 5}}+49^{\frac{1}{\log _{8} 7}}}$
## Solution. $$ \begin{aligned} & \sqrt{\frac{1}{25^{\log _{6} 5}}+49^{\frac{1}{\log _{8} 7}}}=\sqrt{5^{2 \log _{5} 6}+7^{2 \log _{7} 8}}=\sqrt{5^{\log _{5} 6^{2}}+7^{\log _{7} 8^{2}}}= \\ & =\sqrt{6^{2}+8^{2}}=10 \end{aligned} $$ Answer: 10.
10
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,782
7.002. $81^{\frac{1}{\log _{5} 3}}+27^{\log _{9} 36}+3^{\frac{4}{\log _{7} 9}}$.
Solution. $81^{\frac{1}{\log _{5} 3}}+27^{\log _{9} 36}+3^{\frac{4}{\log _{7} 9}}=3^{4 \log _{3} 5}+3^{\frac{3}{2^{2} \log _{3} 36}}+3^{\frac{4}{2} \log _{3} 7}=5^{4}+36^{\frac{3}{2}}+49=$ $=625+216+49=890$. Answer: 890.
890
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,783
7.003. $-\log _{2} \log _{2} \sqrt{\sqrt[4]{2}}$. Translate the above text into English, keeping the original text's line breaks and format, and output the translation result directly. 7.003. $-\log _{2} \log _{2} \sqrt{\sqrt[4]{2}}$.
Solution. $$ -\log _{2} \log _{2} \sqrt{\sqrt[4]{2}}=-\log _{2} \log _{2} 2^{\frac{1}{8}}=-\log _{2} \frac{1}{8} \log _{2} 2=-\log _{2} 2^{-3}=3 $$ Answer: 3.
3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,784
7.004. $-\log _{3} \log _{3} \sqrt[3]{\sqrt[3]{3}}$. 7.004. $-\log _{3} \log _{3} \sqrt[3]{\sqrt[3]{3}}$.
## Solution. $-\log _{3} \log _{3} \sqrt[3]{\sqrt[3]{3}}=-\log _{3} \log _{3} 3^{\frac{1}{9}}=-\log _{3} \frac{1}{9} \log _{3} 3=-\log _{3} 3^{-2}=2$. Answer: 2. ![](https://cdn.mathpix.com/cropped/2024_05_22_fa9db84b44b98ec0a5c7g-351.jpg?height=252&width=684&top_left_y=416&top_left_x=74) ## Solution. ![](https://...
2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,785
7.007. $\left(81^{\frac{1}{4}-\frac{1}{\log _{9} 4}}+25^{\log _{125} 8}\right) \cdot 49^{\log _{7} 2}$.
Solution. $$ \begin{aligned} & \left(81^{\frac{1}{4}-\frac{1}{2} \log _{9} 4}+25^{\log _{125} 8}\right) \cdot 49^{\log _{7} 2}=\left(\frac{81^{\frac{1}{4}}}{\left(9^{2}\right)^{\frac{1}{2} \log _{9} 4}}+5^{2 \log _{5} 32^{3}}\right) \cdot 7^{2 \log _{7} 2}= \\ & =\left(\frac{3}{4}+4\right) \cdot 4=19 \end{aligned} $$ ...
19
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,786
7.008. $\frac{81^{\frac{1}{\log _{5} 9}}+3^{\frac{3}{\log _{\sqrt{6}} 3}}}{409} \cdot\left((\sqrt{7})^{\frac{2}{\log _{25} 7}}-125^{\log _{25} 6}\right)$
## Решение. $$ \frac{81^{\frac{1}{\log _{5} 9}}+3^{\frac{3}{\log _{\sqrt{6}}}}}{409} \cdot\left((\sqrt{7})^{\frac{2}{\log _{25} 7}}-125^{\log _{25} 6}\right)= $$ $=\frac{9^{2 \log _{9} 5}+3^{3 \log _{3} \sqrt{6}}}{409} \cdot\left(\left(7^{\frac{1}{2}}\right)^{2 \log _{7} 25}-5^{3 \log _{5} 26}\right)=\frac{9^{\log _{...
1
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,787
7.009. $\left(N^{\frac{1}{\log _{2} N}} \cdot N^{\frac{1}{\log _{4} N}} \cdot N^{\frac{1}{\log _{8} N}} \cdots N^{\frac{1}{\log _{64} N}}\right)^{\frac{1}{15}}$ (the bases of the logarithms are consecutive natural powers of the number 2).
## Solution. $$ \begin{aligned} & \left(N^{\frac{1}{\log _{2} N}} \cdot N^{\frac{1}{\log _{4} N}} \cdot N^{\frac{1}{\log _{8} N}} \cdots N^{\frac{1}{\log _{512} N}}\right)^{\frac{1}{15}}= \\ & =\left(N^{\log _{N} 2} \cdot N^{\log _{N} 4} \cdot N^{\log _{N} 8} \cdots N^{\log _{N} 512}\right)^{\frac{1}{15}}= \\ & =(2 \c...
8
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,788
7.010. $\left(2^{\log _{\sqrt{2}} a}-3^{\log _{27}\left(a^{2}+1\right)^{\beta}}-2 a\right):\left(7^{4 \log _{49} a}-5^{0.5 \log _{\sqrt{5}} a}-1\right)$
## Solution. $$ \begin{aligned} & \left(2^{\log _{\sqrt{2}} a}-3^{\log _{27}\left(a^{2}+1\right)^{1}}-2 a\right):\left(7^{4 \log _{49} a}-5^{0.5 \log _{\sqrt{5}} a}-1\right)= \\ & =\left(2^{\log _{2} a^{4}}-3^{\log _{3}\left(a^{2}+1\right)}-2 a\right):\left(7^{\log _{7} a^{2}}-5^{\log _{5} a}-1\right)= \\ & =\left(a^{...
^{2}++1
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,789
7.011. $\frac{\log _{a} \sqrt{a^{2}-1} \cdot \log _{1 / a}^{2} \sqrt{a^{2}-1}}{\log _{a^{2}}\left(a^{2}-1\right) \cdot \log _{\sqrt[3]{a}} \sqrt[6]{a^{2}-1}}$.
Solution. $$ \frac{\log _{a} \sqrt{a^{2}-1} \cdot \log _{1 / a}^{2} \sqrt{a^{2}-1}}{\log _{a^{2}}\left(a^{2}-1\right) \cdot \log _{\sqrt[3]{a}} \sqrt[6]{a^{2}-1}}=\frac{\frac{1}{2} \log _{a}\left(a^{2}-1\right) \cdot \frac{1}{4} \log _{a}^{2}\left(a^{2}-1\right)}{\frac{1}{2} \log _{a}\left(a^{2}-1\right) \cdot \frac{1...
\log_{}\sqrt{^{2}-1}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,790
7.013. $\frac{\left(25^{\frac{1}{2 \log _{4} 25}}+2 \log _{2} \log _{2} \log _{2} a^{2 \log _{a} 4}\right) \cdot 4^{-\frac{2}{\log _{3} 4}}-a^{2}}{1-a}$.
## Solution. $$ \frac{\left(25^{\frac{1}{2 \log _{9} 25}}+2 \log _{2} \log _{2} \log _{2} a^{2 \log _{a} 4}\right) \cdot 4^{\frac{2}{\log _{3} 4}}-a^{2}}{1-a}= $$ $$ \begin{aligned} & =\frac{\left(\left(25^{\log _{2} 49}\right)^{\frac{1}{2}}+2 \log _{2} \log _{2} 4\right) \cdot\left(\left(4^{\log _{4} 3}\right)^{-1}-...
1+
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,792
7.014. $\left(\log _{a} b+\log _{b} a+2\right)\left(\log _{a} b-\log _{a b} b\right) \log _{b} a-1$.
Solution. $$ \begin{aligned} & \left(\log _{a} b+\log _{b} a+2\right)\left(\log _{a} b-\log _{a b} b\right) \log _{b} a-1=\left(\log _{a} b+\frac{1}{\log _{a} b}+2\right) \times \\ & \times\left(\log _{a} b-\frac{\log _{a} b}{\log _{a} a b}\right) \frac{1}{\log _{a} b}-1=\frac{\log _{a}^{2} b+2 \log _{a} b+1}{\log _{a...
\log_{}b
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,793
7.015. $\frac{1-\log _{a}^{3} b}{\left(\log _{a} b+\log _{b} a+1\right) \cdot \log _{a} \frac{a}{b}}$.
## Solution. $\frac{1-\log _{a}^{3} b}{\left(\log _{a} b+\log _{b} a+1\right) \cdot \log _{a} \frac{a}{b}}=\frac{\left(1-\log _{a} b\right)\left(1+\log _{a} b+\log _{a}^{2} b\right)}{\left(\log _{a} b+\frac{1}{\log _{a} b}+1\right)\left(\log _{a} a-\log _{a} b\right)}=$ $$ =\frac{\left(1-\log _{a} b\right)\left(1+\lo...
\log_{}b
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,794
7.016. If $\log _{a} 27=b$, then what is $\log _{\sqrt{3}} \sqrt[6]{a}$?
Solution. $\log _{\sqrt{3}} \sqrt[6]{a}=\frac{1}{6} \cdot 2 \log _{3} a=\frac{1}{3 \log _{a} 3}=\frac{1}{\log _{a} 27}=\frac{1}{b}$. Answer: $\frac{1}{b}$.
\frac{1}{b}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,795
7.017. Show that under the conditions $x>0$ and $y>0$, from the equation $x^{2}+4 y^{2}=12 x y$ it follows that $\lg (x+2 y)-2 \lg 2=0.5(\lg x+\lg y)$.
## Solution. From the condition, we have: $(x+2 y)^{2}-2 x \cdot 2 y=12 x y, \quad(x+2 y)^{2}=16 x y$. Taking the logarithm of both sides of the obtained equation with base 10, we get: $$ \begin{aligned} & \lg (x+2 y)^{2}=\lg 16 x y, \quad 2 \lg (x+2 y)=\lg 16+\lg x+\lg y \\ & 2 \lg (x+2 y)=4 \lg 2+\lg x+\lg y, \qua...
proof
Algebra
proof
Yes
Yes
olympiads
false
50,796
7.019. Prove that if $y=2^{x^{2}}$ and $z=2^{y^{2}}$, then $x= \pm \sqrt{0.5 \log _{2} \log _{2} z}$, and specify all $z$ for which $x$ takes real values.
Solution. Given $y>0$ and $z>0$. Taking the logarithm of both sides of the equation with base 2, we get $\log _{2} y=\log _{2} 2^{x^{2}}, \log _{2} y=x^{2}$, from which $x= \pm \sqrt{\log _{2} y}$. Similarly, $z=2^{y^{2}} \Rightarrow y=\sqrt{\log _{2} z}$. Thus, $x= \pm \sqrt{\log _{2} \sqrt{\log _{2} z}}= \pm \sqrt{...
z\geq2
Algebra
proof
Yes
Yes
olympiads
false
50,797
7.020. $\left(1+\frac{1}{2 x}\right) \log 3+\log 2=\log \left(27-3^{1 / x}\right)$.
Solution. D: $\quad\left\{\begin{array}{l}x \neq 0, \\ 27-3^{1 / x}>0 .\end{array}\right.$ $\lg 3^{1+\frac{1}{2 x}}+\lg 2=\lg \left(27-3^{\frac{1}{x}}\right) \lg \left(2 \cdot 3^{1+\frac{1}{2 x}}\right)=\lg \left(27-3^{\frac{1}{x}}\right)$ $2 \cdot 3^{1+\frac{1}{2 x}}=27-3^{\frac{1}{x}}, 3^{\frac{1}{x}}+6 \cdot 3^{\f...
\frac{1}{2}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,798
7.021. $3 \log _{5} 2+2-x=\log _{5}\left(3^{x}-5^{2-x}\right)$. 7.021. $3 \log _{5} 2+2-x=\log _{5}\left(3^{x}-5^{2-x}\right)$.
Solution. Domain of definition: $3^{x}-5^{2-x}>0$. $\log _{5} 8+2 \log _{5} 5-\log _{5}\left(3^{x}-25 \cdot 5^{-x}\right)=x \Leftrightarrow \log _{5} \frac{8 \cdot 25}{3^{x}-25 \cdot 5^{-x}}=x$, from which $\frac{200}{3^{x}-25 \cdot 5^{-x}}=5^{x} \Leftrightarrow 15^{x}=15^{2}$. Therefore, $x=2$. Answer: 2.
2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,799
7.022. $\sqrt{\log _{3} x^{9}}-4 \log _{9} \sqrt{3 x}=1$.
Solution. Domain of definition: $\left\{\begin{array}{l}x>0, \\ \log _{3} x>0, x>1\end{array}\right.$ $$ \begin{aligned} & \sqrt{\log _{3} x^{9}}=1+4 \log _{9} \sqrt{3 x} \Leftrightarrow \sqrt{9 \log _{3} x}=1+\log _{3} 3 x \Leftrightarrow \\ & \Leftrightarrow \sqrt{9 \log _{3} x}=1+\log _{3} 3+\log _{3} x \Leftright...
3;81
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,800
7.024. $\lg 5+\lg (x+10)=1-\lg (2 x-1)+\lg (21 x-20)$.
## Solution. Domain of definition: $\left\{\begin{array}{l}x+10>0, \\ 2 x-1>0, \\ 21 x-20>0,\end{array} \quad x>\frac{20}{21}\right.$. $$ \begin{aligned} & \lg 5+\lg (x+10)=\lg 10-\lg (2 x-1)+\lg (21 x-20) \Leftrightarrow \lg 5(x+10)= \\ & =\lg \frac{10 \cdot(21 x-20)}{2 x-1} \Rightarrow 5(x+10)=\frac{10 \cdot(21 x-2...
1.5;10
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,801
7.028. $5^{2\left(\log _{5} 2+x\right)}-2=5^{x+\log _{5} 2}$.
## Solution. $\left(5^{x+\log _{5} 2}\right)^{2}-5^{x+\log _{5} 2}-2=0$; solving this equation as a quadratic equation in terms of $5^{x+\log _{5} 2}$, we find $5^{x+\log _{5} 2}=-1$ and $5^{x+\log _{5} 2}=2 ; 5^{x+\log _{5} 2}=-1$ has no solutions. Thus, $$ 5^{x+\log _{5} 2}=2 \Rightarrow \log _{5} 5^{x+\log _{5} 2...
0
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,802
7.029. $0.25^{\log _{2} \sqrt{x+3}-0.5 \log _{2}\left(x^{2}-9\right)}=\sqrt{2(7-x)}$.
## Solution. Domain of definition: $\quad\left\{\begin{array}{l}x+3>0, \\ x^{2}-9>0.33 . \Rightarrow x_{1}=5, x_{2}=-1 ; x_{2}=-1 \text{ does not fit the domain of definition.}\end{array}\right.$ Answer: 5.
5
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,803
7.030. $x \lg \sqrt[5]{5^{2 x-8}}-\lg 25=0$. Translate the above text into English, please retain the original text's line breaks and format, and output the translation result directly. 7.030. $x \lg \sqrt[5]{5^{2 x-8}}-\lg 25=0$.
## Solution. $x \lg 5^{\frac{2 x-8}{5}}=\lg 25, \lg 5^{\frac{(2 x-8) x}{5}}=\lg 5^{2}, 5^{\frac{2 x^{2}-8 x}{5}}=5^{2}$, $\frac{2 x^{2}-8 x}{5}=2, x^{2}-4 x-5=0$, from which $x_{1}=5, x_{2}=-1$. Answer: $5; -1$.
5;-1
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,804
7.031. $\log _{5}(x-2)+\log _{\sqrt{5}}\left(x^{3}-2\right)+\log _{0.2}(x-2)=4$.
## Solution. Domain of definition: $\quad x-2>0, x>2$. From the condition we have $$ \log _{5}(x-2)+2 \log _{5}\left(x^{3}-2\right)-\log _{5}(x-2)=4, \log _{5}\left(x^{3}-2\right)=2 $$ from which $x^{3}-2=25, x^{3}=27$. Then $x=3$. Answer: 3.
3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,805
7.034. $\lg \left(3^{x}-2^{4-x}\right)=2+0.25 \lg 16-0.5 x \lg 4$.
Solution. Domain of definition: $3^{x}-2^{4-x}>0$. From the condition $$ \begin{aligned} & \lg \left(3^{x}-2^{4-x}\right)=\lg 100+\lg 2-\lg 2^{x} \Rightarrow \lg \left(3^{x}-2^{4-x}\right)=\lg \frac{100 \cdot 2}{2^{x}} \\ & 3^{x}-2^{4-x}=\frac{200}{2^{x}} \end{aligned} $$ From here $6^{x}=216$, hence $x=3$. Answer...
3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,806
7.035. $\log _{3}\left(81^{x}+3^{2 x}\right)=3 \log _{27} 90$.
## Solution. From the condition $\log _{3}\left(81^{x}+3^{2 x}\right)=\log _{3} 90, 9^{2 x}+9^{x}-90=0$, from which we find $9^{x}=-10$, which is not suitable, or $9^{x}=9$, from which we have $x=1$. Answer: 1.
1
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,807
7.036. $3 x-\log _{6} 8^{x}=\log _{6}\left(3^{3 x}+x^{2}-9\right)$ 7.036. $3 x-\log _{6} 8^{x}=\log _{6}\left(3^{3 x}+x^{2}-9\right)$
## Solution. Domain of definition: $3^{3 x}+x^{2}-9>0$. From the condition $3 x=\log _{6} 8^{x}+\log _{6}\left(3^{3 x}+x^{2}-9\right) 3 x=\log _{6} 8^{x}\left(3^{3 x}+x^{2}-9\right)$, hence $6^{3 x}=8^{x}\left(3^{3 x}+x^{2}-9\right) 3^{3 x}=3^{3 x}+x^{2}-9 \Leftrightarrow x^{2}=9$. Then $x_{1,2}= \pm 3$. Answer: $-3...
-3;3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,808
7.037. $\log _{6}\left(3^{x^{2}}+1\right)-\log _{6}\left(3^{2-x^{2}}+9\right)=\log _{6} 2-1$.
## Solution. From the condition $$ \begin{aligned} & \log _{6}\left(3^{x^{2}}+1\right)-\log _{6}\left(3^{2-x^{2}}+9\right)=\log _{6} 2-\log _{6} 6, \log _{6} \frac{3^{x^{2}}+1}{3^{2-x^{2}}+9}=\log _{6} \frac{2}{6} \\ & \frac{3^{x^{2}}+1}{9 \cdot 3^{-x^{2}}+9}=\frac{2}{6}, 3^{2 x^{2}}-2 \cdot 3^{x^{2}}-3=0 . \end{alig...
-1;1
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,809
7.038. $\lg \left(625 \sqrt[5]{5^{x^{2}-20 x+55}}\right)=0$. 7.038. $\lg \left(625 \sqrt[5]{5^{x^{2}-20 x+55}}\right)=0$.
## Solution. From the condition, we have $625 \cdot 5^{\frac{x^{2}-20 x+55}{5}}=1.5^{\frac{x^{2}-20 x+55}{5}}=5^{-4}$, from which $\frac{x^{2}-20 x+55}{5}=-4, x^{2}-20 x+75=0$. Then $x_{1}=5 ; x_{2}=15$. Answer: $5 ; 15$.
5;15
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,810
7.039. $\lg \left(10^{\lg \left(x^{2}-21\right)}\right)-2=\lg x-\lg 25$.
## Solution. Domain of definition: $\left\{\begin{array}{l}x^{2}-21>0, \\ x>0,\end{array} x>\sqrt{21}\right.$. From the condition we have $$ \lg \left(x^{2}-21\right)-\lg 100=\lg x-\lg 25, \lg \frac{x^{2}-21}{100}=\lg \frac{x}{25}, \quad \frac{x^{2}-21}{100}=\frac{x}{25} $$ We obtain the quadratic equation $x^{2}-4...
7
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,811
7.040. $\lg \left(x^{2}+1\right)=2 \lg ^{-1}\left(x^{2}+1\right)-1$. 7.040. $\lg \left(x^{2}+1\right)=2 \lg ^{-1}\left(x^{2}+1\right)-1$.
## Solution. Domain of definition: $x \neq 0$. $$ \lg \left(x^{2}+1\right)=\frac{2}{\lg \left(x^{2}+1\right)}-1, \lg ^{2}\left(x^{2}+1\right)+\lg \left(x^{2}+1\right)-2=0 $$ Solving this equation as a quadratic equation in terms of $\lg \left(x^{2}+1\right)$, we find $\lg \left(x^{2}+1\right)=-2$ and $\lg \left(x^{2...
-3;3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,812
7.041. $\lg \sqrt{5^{x(13-x)}}+11 \lg 2=11$.
Solution. $\lg 5^{\frac{x(13-x)}{2}}+\lg 2^{11}=11, \lg \left(5^{\frac{x(13-x)}{2}} \cdot 2^{11}\right)=11$ From here we have $5^{\frac{x(13-x)}{2}} \cdot 2^{11}=10^{11}, 5^{\frac{x(13-x)}{2}}=5^{11}$. Then $\frac{x(13-x)}{2}=11$, $x^{2}-13 x+22=0$, from which $x_{1}=2 ; x_{2}=11$. Answer: $2 ; 11$.
2;11
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,813
7.042. $x(\lg 5-1)=\lg \left(2^{x}+1\right)-\lg 6$. Translate the above text into English, please retain the original text's line breaks and format, and output the translation result directly. 7.042. $x(\lg 5-1)=\lg \left(2^{x}+1\right)-\lg 6$.
Solution. $$ \begin{aligned} & x(\lg 5-\lg 10)=\lg \left(2^{x}+1\right)-\lg 6, \quad x \lg \frac{5}{10}=\lg \frac{2^{x}+1}{6} \\ & \lg 2^{-x}=\lg \frac{2^{x}+1}{6}, 2^{-x}=\frac{2^{x}+1}{6}, 2^{2 x}+2^{x}-6=0 \end{aligned} $$ Solving this equation as a quadratic in terms of $2^{x}$, we find $2^{x}=-3$ (not valid), $2...
1
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,814
7.043. $\lg \left(81 \cdot \sqrt[3]{3^{x^{2}-8 x}}\right)=0$. 7.043. $\lg \left(81 \cdot \sqrt[3]{3^{x^{2}-8 x}}\right)=0$.
## Solution. We have $81 \cdot \sqrt[3]{3^{x^{2}-8 x}}=1, 3^{\frac{x^{2}-8 x}{3}}=3^{-4}$, from which $\frac{x^{2}-8 x}{3}=-4, x^{2}-8 x+12=0$; $x_{1}=2 ; x_{2}=6$. Answer: $2 ; 6$.
2;6
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,815
7.044. $\log _{x} 9 x^{2} \cdot \log _{3}^{2} x=4$.
## Solution. Domain of definition: $\quad 0<x \neq 1$. ## We have $$ \frac{\log _{3} 9 x^{2}}{\log _{3} x} \cdot \log _{3}^{2} x=4, \quad\left(\log _{3} 9+\log _{3} x^{2}\right) \log _{3} x=4, \log _{3}^{2} x+\log _{3} x-2=0 $$ Solving this equation as a quadratic equation in terms of $\log _{3} x$, we find $\left(...
\frac{1}{9};3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,816
7.045. $\log _{5}(3 x-11)+\log _{5}(x-27)=3+\log _{5} 8$.
Solution. Domain of definition: $\left\{\begin{array}{l}3 x-11>0, \\ x-27>0,\end{array} \quad x>27\right.$. ## We have $$ \begin{aligned} & \log _{5}(3 x-11)+\log _{5}(x-27)=\log _{5} 125+\log _{5} 8 \\ & \log _{5}(3 x-11) \cdot(x-27)=\log _{5}(125 \cdot 8) \quad(3 x-11)(x-27)=125 \cdot 8 \\ & 3 x^{2}-92 x-703=0 \en...
37
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,817
7.046. $\lg (5-x)+2 \lg \sqrt{3-x}=1$. 7.046. $\lg (5-x)+2 \lg \sqrt{3-x}=1$.
## Solution. Domain of definition: $\quad\left\{\begin{array}{l}5-x>0, \\ 3-x>0,\end{array}, x<3\right.$. We have $\lg (5-x)+\lg (3-x)=1, \lg (5-x)(3-x)=1$, hence $(5-x)(3-x)=10$, $x^{2}-8 x+5=0$. Then $x_{1}=4-\sqrt{11}, x_{2}=4+\sqrt{11} ; x_{2}=4+\sqrt{11}$ does not satisfy the domain of definition. Answer: $4-\s...
4-\sqrt{11}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,818
7.047. Find the natural number $n$ from the equation $$ 3^{2} \cdot 3^{5} \cdot 3^{8} \cdots 3^{3 n-1}=27^{5} $$
## Solution. $3^{2+5+8+\ldots+3 n-1}=3^{15}, 2+5+8+\ldots+3 n-1=15$. On the left side of the equation, we have the sum of the terms of an arithmetic progression $S_{k}$, where $a_{1}=2, d=3, a_{k}=3 n-1, k=\frac{a_{k}-a_{1}}{d}+1=\frac{3 n-1-2}{3}+1=n$. Then $S_{k}=\frac{a_{1}+a_{k}}{2} \cdot k=\frac{2+3 n-1}{2} \cd...
3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,819
7.048. $0.5\left(\lg \left(x^{2}-55 x+90\right)-\lg (x-36)\right)=\lg \sqrt{2}$.
## Solution. Domain of definition: $\left\{\begin{array}{l}x^{2}-55 x+90>0 \\ x-36>0\end{array}\right.$ From the condition $$ \begin{aligned} & 0.5\left(\lg \left(x^{2}-55 x+90\right)-\lg (x-36)\right)=0.5 \lg 2, \lg \frac{x^{2}-55 x+90}{x-36}=\lg 2 \\ & \frac{x^{2}-55 x+90}{x-36}=2 \end{aligned} $$ We have $x^{2}-...
54
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,820
7.049. $\lg (5-x)-\frac{1}{3} \lg \left(35-x^{3}\right)=0$.
## Solution. Domain of definition: $\left\{\begin{array}{l}5-x>0, \\ 35-x^{3}>0,\end{array}, x<\sqrt[3]{35}\right.$. From the condition, we have $3 \lg (5-x)=\lg \left(35-x^{3}\right), \lg (5-x)^{3}=\lg \left(35-x^{3}\right)$, hence $(5-x)^{3}=35-x^{3}, x^{2}-5 x+6=0$. Therefore, $x_{1}=2, x_{2}=3$. Answer: $2 ; 3$.
2;3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,821
7.050. $\log _{2} \frac{x-5}{x+5}+\log _{2}\left(x^{2}-25\right)=0$.
## Solution. Domain of definition: $\frac{x-5}{x+5}>0$ or $x \in(-\infty ;-5) \cup(5 ; \infty)$. We have $\log _{2} \frac{(x-5)\left(x^{2}-25\right)}{x+5}=0,(x-5)^{2}=1$, from which $x-5=-1$ or $x-5=1$. Then $x_{1}=4, x_{2}=6 ; x_{1}=4$ does not fit the domain of definition. Answer: 6.
6
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,822
7.051. $\frac{\lg 8-\lg (x-5)}{\lg \sqrt{x+7}-\lg 2}=-1$.
## Solution. Domain of definition: $\left\{\begin{array}{l}x-5>0, \\ x+7>0, \quad x>5 . \\ \sqrt{x+7} \neq 2,\end{array}\right.$ ## From the condition $$ \begin{aligned} & \lg 8-\lg (x-5)=\lg 2-\lg \sqrt{x+7}, \quad \lg \frac{8}{x-5}=\lg \frac{2}{\sqrt{x+7}} \\ & \frac{8}{x-5}=\frac{2}{\sqrt{x+7}}, \quad 4 \sqrt{x+7...
29
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,823
7.052. $\log _{0.5}^{2} 4 x+\log _{2} \frac{x^{2}}{8}=8$.
## Solution. Domain of definition: $x>0$. We have $$ \begin{aligned} & \log _{2}^{2} 4 x+\log _{2} \frac{x^{2}}{8}-8=0, \quad\left(\log _{2} 4+\log _{2} x\right)^{2}+\log _{2} x^{2}-\log _{2} 8-8=0 \\ & \log _{2}^{2} x+6 \log _{2} x-7=0 \end{aligned} $$ Solving this equation as a quadratic equation in terms of $\lo...
\frac{1}{128};2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,824
7.053. $\lg (\lg x)+\lg \left(\lg x^{3}-2\right)=0$. Translate the above text into English, keeping the original text's line breaks and format, and output the translation result directly. 7.053. $\lg (\lg x)+\lg \left(\lg x^{3}-2\right)=0$.
Solution. Domain of definition: $\left\{\begin{array}{l}\lg x>0, \\ \lg x^{3}-2>0,\end{array} \quad x>\sqrt[3]{100}\right.$. From the condition we have $\lg \left(\lg x \cdot\left(\lg x^{3}-2\right)\right)=0, \quad \lg x(3 \lg x-2)=1$, $3 \lg ^{2} x-2 \lg x-1=0$. Solving this equation as a quadratic equation in te...
10
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,825
7.054. $\log _{2} x+\log _{4} x+\log _{8} x=11$.
## Solution. Domain: $x>0$. We have $\log _{2} x+\frac{1}{2} \log _{2} x+\frac{1}{3} \log _{2} x=11, \log _{2} x=6$, from which $x=2^{6}=64$. Answer: 64.
64
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,826
7.055. $\log _{3}\left(3^{x}-8\right)=2-x$. Translate the above text into English, please keep the original text's line breaks and format, and output the translation result directly. 7.055. $\log _{3}\left(3^{x}-8\right)=2-x$.
Solution. Domain of definition: $3^{x}-8>0$. By the definition of logarithm, we have $3^{x}-8=3^{2-x}, 3^{x}-8=\frac{9}{3^{x}}$, $3^{2 x}-8 \cdot 3^{x}-9=0$, from which, solving this equation as a quadratic equation in terms of $3^{x}$, we find $3^{x}=-1, \varnothing$; or $3^{x}=9$, from which $x=2$. Answer: 2.
2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,827
7.056. $7^{\lg x}-5^{\lg x+1}=3 \cdot 5^{\lg x-1}-13 \cdot 7^{\lg x-1}$.
## Solution. Domain: $x>0$. From the condition $$ 7^{\lg x}-5 \cdot 5^{\lg x}=\frac{3}{5} \cdot 5^{\lg x}-\frac{13}{7} \cdot 7^{\lg x}, \quad 35 \cdot 7^{\lg x}+65 \cdot 7^{\lg x}=21 \cdot 5^{\lg x}+175 \cdot 5^{\lg x}, $$ $100 \cdot 7^{\lg x}=196 \cdot 5^{\lg x},\left(\frac{7}{5}\right)^{\lg x}=\left(\frac{7}{5}\r...
100
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,828
7.057. $5^{x+6}-3^{x+7}=43 \cdot 5^{x+4}-19 \cdot 3^{x+5}$.
Solution. We have $5^{6} \cdot 5^{x}-43 \cdot 5^{4} \cdot 5^{x}=3^{7} \cdot 3^{x}-19 \cdot 3^{5} \cdot 3^{x},\left(\frac{5}{3}\right)^{x}=\left(\frac{5}{3}\right)^{-3}$, from which $x=-3$. Answer: -3.
-3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,829
7.058. $\frac{\log _{5}(\sqrt{2 x-7}+1)}{\log _{5}(\sqrt{2 x-7}+7)}=0.5$.
## Solution. Domain of definition: $2 x-7 \geq 0, x \geq \frac{7}{2}$. From the condition $\log _{5}(\sqrt{2 x-7}+1)=\frac{1}{2} \log _{5}(\sqrt{2 x-7}+7) \quad \log _{5}(\sqrt{2 x-7}+1)=\log _{5} \sqrt{\sqrt{2 x-7}+7}$, hence $\sqrt{2 x-7}+1=\sqrt{\sqrt{2 x-7}+7} \Rightarrow(\sqrt{2 x-7})^{2}+2 \sqrt{2 x-7}+1=\sqr...
5.5
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,830
7.060. $\sqrt{2^{x} \cdot \sqrt[3]{4^{x} \cdot 0.125^{1 / x}}}=4 \sqrt[3]{2}$.
Solution. Domain of definition: $x \neq 0$. Rewrite the equation as $$ 2^{\frac{x}{2}} \cdot 2^{\frac{x}{3}} \cdot 2^{-\frac{1}{2 x}}=2^{2} \cdot 2^{\frac{1}{3}}, 2^{\frac{x}{2}+\frac{x}{3}-\frac{1}{2 x}}=2^{2+\frac{1}{3}} $$ from which $\frac{x}{2}+\frac{x}{3}-\frac{1}{2 x}=\frac{7}{3}, 5 x^{2}-14 x-3=0$. Then $...
-\frac{1}{5};3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,831
7.061. $\sqrt{2} \cdot 0.5^{\frac{5}{5^{x}+10}}-16^{\left.\frac{1}{2(\sqrt{x}+1}\right)}=0$.
## Solution. Domain of definition: $x \geq 0$. From the condition $$ 2^{\frac{1}{2}} \cdot 2^{-\frac{5}{4 \sqrt{x}+10}}=2^{\frac{2}{\sqrt{x}+1}}, 2^{\frac{1}{2}-\frac{5}{4 \sqrt{x}+10}}=2^{\frac{2}{\sqrt{x}+1}} $$ it follows that $$ \frac{1}{2}-\frac{5}{4 \sqrt{x}+10}=\frac{2}{\sqrt{x}+1} \Rightarrow(\sqrt{x})^{2}...
25
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,832
7.062. $8^{\frac{x-3}{3 x-7}} \sqrt[3]{\sqrt{0.25^{\frac{3 x-1}{x-1}}}}=1$.
Solution. Domain of definition $\left\{\begin{array}{l}x \neq 1, \\ x \neq \frac{7}{3} .\end{array}\right.$ Rewrite the equation as $$ 2^{\frac{3 x-9}{3 x-7}} \cdot 2^{-\frac{3 x-1}{3 x-3}}=2^{0}, 2^{\frac{3 x-9}{3 x-7}-\frac{3 x-1}{3 x-3}}=2^{0} $$ from which $$ \frac{3 x-9}{3 x-7}-\frac{3 x-1}{3 x-3}=0 \Rightarr...
\frac{5}{3}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,833
7.064. $0.6^{x}\left(\frac{25}{9}\right)^{x^{2}-12}=\left(\frac{27}{125}\right)^{3}$.
Solution. We have $$ \begin{aligned} & \left(\frac{3}{5}\right)^{x}\left(\frac{3}{5}\right)^{-2 x^{2}+24}=\left(\frac{3}{5}\right)^{9},\left(\frac{3}{5}\right)^{-2 x^{2}+x+24}=\left(\frac{3}{5}\right)^{9} \\ & -2 x^{2}+x+24=9 ; 2 x^{2}-x-15=0 \end{aligned} $$ from which $x_{1}=-\frac{5}{2}, x_{2}=3$. Answer: $-\fra...
-\frac{5}{2};3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,834
7.066. $2^{\frac{1}{\sqrt{x}-1}} \cdot 0.5^{\frac{1}{\sqrt{x}+1}}=4^{\frac{\sqrt{x}}{x+\sqrt{x}}}$
Solution. Domain of definition: $0<x \neq 1$. We have: $2^{\frac{1}{\sqrt{x}-1}} \cdot 2^{-\frac{1}{\sqrt{x}+1}}=2^{\frac{2 \sqrt{x}}{x+\sqrt{x}}}, 2^{\frac{1}{\sqrt{x}-1}-\frac{1}{\sqrt{x}+1}}=2^{\frac{2 \sqrt{x}}{x+\sqrt{x}}}$. Then $\frac{1}{\sqrt{x}-1}-\frac{1}{\sqrt{x}+1}=\frac{2 \sqrt{x}}{x+\sqrt{x}}, x-\sqrt{...
4
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,835
7.067. $2,5^{\frac{4+\sqrt{9-x}}{\sqrt{9-x}}} \cdot 0,4^{1-\sqrt{9-x}}=5^{10} \cdot 0,1^{5}$.
## Solution. Domain of definition: $9-x>0, x<9$. Rewrite the equation as $$ \left(\frac{5}{2}\right)^{\frac{4+\sqrt{9-x}}{\sqrt{9-x}}} \cdot\left(\frac{5}{2}\right)^{\sqrt{9-x}-1}=\left(\frac{5}{2}\right)^{5},\left(\frac{5}{2}\right)^{\frac{4+\sqrt{9-x}}{\sqrt{9-x}}+\sqrt{9-x}-1}=\left(\frac{5}{2}\right)^{5} $$ The...
-7,8
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,836
7.068. $2^{x^{2}-1}-3^{x^{2}}=3^{x^{2}-1}-2^{x^{2}+2}$.
## Solution. We have $\frac{2^{x^{2}}}{2}+4 \cdot 2^{x^{2}}=\frac{3^{x^{2}}}{3}+3^{x^{2}}, \frac{9}{2} \cdot 2^{x^{2}}=\frac{4}{3} \cdot 3^{x^{2}},\left(\frac{2}{3}\right)^{x^{2}}=\left(\frac{2}{3}\right)^{3}$. Then $x^{2}=3$, from which $x_{1}=-\sqrt{3}, x_{2}=\sqrt{3}$. Answer: $-\sqrt{3} ; \sqrt{3}$.
-\sqrt{3};\sqrt{3}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,837
7.069. $\log _{\sqrt{5}}\left(4^{x}-6\right)-\log _{\sqrt{5}}\left(2^{x}-2\right)=2$.
Solution. Domain of Definition (DOD): $\left\{\begin{array}{l}4^{x}-6>0 \\ 2^{x}-2>0 .\end{array}\right.$ We have $\log _{\sqrt{5}} \frac{4^{x}-6}{2^{x}-2}=2, \frac{2^{2 x}-6}{2^{2}-2}=5,2^{2 x}-5 \cdot 2^{x}+4=0$. Solving this equation as a quadratic in terms of $2^{x}$, we find $\left(2^{x}\right)=1$, from which we...
2
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,838
7.070. $4^{\log _{9} x^{2}}+\log _{\sqrt{3}} 3=0.2\left(4^{2+\log _{9} x}-4^{\log _{9} x}\right)$.
## Solution. Domain of definition: $x>0$. Rewrite the equation as $4^{2 \log _{9} x}+2 \log _{3} 3=0.2\left(16 \cdot 4^{\log _{9} x}-4^{\log _{9} x}\right) \quad 4^{2 \log _{9} x}-3 \cdot 4^{\log _{9} x}+2=0$. Solving this equation as a quadratic equation in terms of $4^{\log _{9} x}$, we find $\left(4^{\log _{9} x...
1;3
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,839
7.071. $3 \cdot 5^{2 x-1}-2 \cdot 5^{x-1}=0.2$.
## Solution. From the condition $3 \cdot 5^{2 x}-2 \cdot 5^{x}=1,3 \cdot 5^{2 x}-2 \cdot 5^{x}-1=0$. Solving this equation as a quadratic in terms of $5^{x}$, we get $5^{x}=-\frac{1}{3}, \varnothing$; or $5^{x}=1$, from which $x=0$. Answer: 0.
0
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,840
7.072. $10^{\frac{2}{x}}+25^{\frac{1}{x}}=4.25 \cdot 50^{\frac{1}{x}}$.
Solution. Domain of definition: $x \neq 0$. Dividing both sides of the equation by $25^{\frac{1}{x}}$, we get $2^{\frac{2}{x}}-4.25\left(2^{\frac{1}{x}}\right)+1=0$, from which, solving the equation as a quadratic in terms of $2^{\frac{1}{x}}$, we obtain $\left(2^{\frac{1}{x}}\right)=\frac{1}{4}$, hence $\left(\frac{...
x_{1}=-\frac{1}{2};x_{2}=\frac{1}{2}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,841
7.073. $9^{x^{2}-1}-36 \cdot 3^{x^{2}-3}+3=0$.
Solution. We have $\frac{9^{x^{2}}}{9}-36 \cdot \frac{3^{x^{2}}}{27}+3=0, \quad 3^{2 x^{2}}-12 \cdot 3^{x^{2}}+27=0$. Solving this equation as a quadratic in terms of $3^{x^{2}}$, we get $3^{x^{2}}=3$, from which $x^{2}=1, x_{1,2}= \pm 1$, or $3^{x^{2}}=9$, from which $x^{2}=2, x_{3,4}= \pm \sqrt{2}$. Answer: $-\sqrt...
-\sqrt{2};-1;1;\sqrt{2}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,842
7.076. $9^{\sqrt{x-5}}-27=6 \cdot 3^{\sqrt{x-5}}$. 7.076. $9^{\sqrt{x-5}}-27=6 \cdot 3^{\sqrt{x-5}}$.
Solution. Domain of definition: $x-5 \geq 0, x \geq 5$. $$ 3^{2 \sqrt{x-5}}-6 \cdot 3^{\sqrt{x-5}}-27=0 $$ We solve the equation as a quadratic equation in terms of $3^{\sqrt{x-5}}$. We have $3^{\sqrt{x-5}}=-3$. (not suitable) or $3^{\sqrt{x-5}}=9$, from which $\sqrt{x-5}=2$, or $x-5=4$. Then $x=9$. Answer: 9.
9
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,844
7.077. $17 \cdot 2^{\sqrt{x^{2}-8 x}}-8=2 \cdot 4^{\sqrt{x^{2}-8 x}}$.
Solution. Domain of definition: $x^{2}-8 x \geq 0, x \in(-\infty ; 0] \cup[8 ;+\infty)$ We have $2 \cdot 2^{2 \sqrt{x^{2}-8 x}}-17 \cdot 2^{\sqrt{x^{2}-8 x}}+8=0$. Solving this equation as a quadratic equation in terms of $2^{\sqrt{x^{2}-8 x}}$, we get $2^{\sqrt{x^{2}-8 x}}=2^{-1}$, from which $\sqrt{x^{2}-8}= -1, \v...
-1;9
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,845
7.078. $8^{\frac{2}{x}}-2^{\frac{3 x+3}{x}}+12=0$. 7.078. $8^{\frac{2}{x}}-2^{\frac{3 x+3}{x}}+12=0$.
Solution. Domain of definition: $x \neq 0$. Rewrite the equation as $$ 2^{\frac{6}{x}}-2^{3+\frac{3}{x}}+12=0,\left(2^{\frac{3}{x}}\right)^{2}-8 \cdot 2^{\frac{3}{x}}+12=0 $$ Solving this equation as a quadratic in terms of $2^{\frac{3}{x}}$, we get $$ \begin{aligned} & \left(2^{\frac{3}{x}}\right)_{1}=2, \text { ...
3;\log_{6}8
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,846
7.079. $2 \log _{x} 27-3 \log _{27} x=1$.
Solution. Domain of definition: $0<x \neq 1$. Let's switch to base 27. We have $$ \frac{2}{\log _{27} x}-3 \log _{27} x-1=0 \Rightarrow 3 \log _{27}^{2} x+\log _{27} x-2=0 $$ Solving this equation as a quadratic equation in terms of $\log _{27} x$, we get $\left(\log _{27} x\right)_{1}=-1$, from which $x_{1}=\frac{...
\frac{1}{27};9
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,847
7.080. $\lg (\sqrt{6+x}+6)=\frac{2}{\log _{\sqrt{x}} 10}$.
Solution. Domain of definition: $\left\{\begin{array}{l}6+x \geq 0, \\ x>0, \\ x \neq 1,\end{array} \quad 0<x \neq 1\right.$. We will switch to base 10. We have $\lg (\sqrt{6+x}+6)=2 \lg \sqrt{x}, \quad \lg (\sqrt{6+x}+6)=\lg x$. Then $\sqrt{6+x}+6=x, \sqrt{6+x}=x-6 \Rightarrow\left\{\begin{array}{l}x^{2}-13 x+30=0...
10
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,848
7.081. $\log _{5} x+\log _{x} 25=\operatorname{ctg}^{2} \frac{25 \pi}{6}$.
## Solution. Domain of definition: $0<x \neq 1$. Switch to base 5. We have $$ \begin{aligned} & \log _{5} x+\frac{2}{\log _{5} x}=\left(\operatorname{ctg}\left(4 \pi+\frac{\pi}{6}\right)\right)^{2}, \log _{5} x+\frac{2}{\log _{5} x}=3 \Rightarrow \\ & \Rightarrow \log _{5}^{2} x-3 \log _{5} x+2=0 \end{aligned} $$ S...
5;25
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,849
7.082. $x^{\frac{\lg x+5}{3}}=10^{5+\lg x}$.
Solution. Domain of definition: $0<x \neq 1$. Taking the logarithm of both sides of the equation with base 10, we have $$ \lg x^{\frac{\lg x+5}{3}}=\lg 10^{5+\lg x}, \frac{\lg x+5}{3} \lg x=(5+\lg x) \lg 10, \lg ^{2} x+2 \lg x-15=0 $$ Solving this equation as a quadratic equation in terms of $\lg x$, we get $(\lg x...
10^{-5};10^{3}
Algebra
math-word-problem
Yes
Yes
olympiads
false
50,850