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## Problem Statement Calculate the definite integral: $$ \int_{0}^{4} e^{\sqrt{(4-x) /(4+x)}} \cdot \frac{d x}{(4+x) \sqrt{16-x^{2}}} $$
## Solution $$ \int_{0}^{4} e^{\sqrt{(4-x) /(4+x)}} \cdot \frac{d x}{(4+x) \sqrt{16-x^{2}}}= $$ Let's make the substitution: $$ \begin{aligned} & t=\sqrt{\frac{4-x}{4+x}} \\ & d t=\frac{1}{2 \sqrt{\frac{4-x}{4+x}}} \cdot \frac{-4-x-4+x}{(4+x)^{2}} d x=-4 \sqrt{\frac{4+x}{4-x}} \cdot \frac{d x}{(4+x)^{2}}=-4 \frac{4+...
\frac{1}{4}\cdot(e-1)
Calculus
math-word-problem
Yes
Yes
olympiads
false
45,996
## Problem Statement Calculate the definite integral: $$ \int_{1 / 8}^{1} \frac{15 \sqrt{x+3}}{(x+3)^{2} \sqrt{x}} d x $$
## Solution $$ \int_{1 / 8}^{1} \frac{15 \sqrt{x+3}}{(x+3)^{2} \sqrt{x}} d x=\int_{1 / 8}^{1} \frac{15}{(x+3) \sqrt{(x+3) x}} d x= $$ Substitution: $$ \begin{aligned} & t=\sqrt{\frac{x+3}{x}} \\ & d t=\frac{1}{2} \sqrt{\frac{x}{x+3}} \cdot \frac{1 \cdot x-(x+3) \cdot 1}{x^{2}} d x=\frac{1}{2} \sqrt{\frac{x}{x+3}} \c...
3
Calculus
math-word-problem
Yes
Yes
olympiads
false
45,997
## Problem Statement Calculate the definite integral: $$ \int_{-5 / 3}^{1} \frac{\sqrt[3]{3 x+5}+2}{1+\sqrt[3]{3 x+5}} d x $$
## Solution $$ \int_{-5 / 3}^{1} \frac{\sqrt[3]{3 x+5}+2}{1+\sqrt[3]{3 x+5}} d x $$ Perform the variable substitution: $$ \begin{aligned} & t=\sqrt[3]{3 x+5} \\ & x=\frac{t^{3}-5}{3} \\ & d x=t^{2} d t \end{aligned} $$ Recalculate the limits of integration: $$ \begin{aligned} & x_{1}=-\frac{5}{3} \Rightarrow t_{1}...
\frac{8}{3}+\ln3
Calculus
math-word-problem
Yes
Yes
olympiads
false
45,998
## Problem Statement Calculate the definite integral: $$ \int_{2}^{3} \sqrt{\frac{3-2 x}{2 x-7}} d x $$
## Solution $$ \int_{2}^{3} \sqrt{\frac{3-2 x}{2 x-7}} d x= $$ Substitution: $$ \begin{aligned} & t=\sqrt{\frac{3-2 x}{2 x-7}} \Rightarrow t^{2}=\frac{3-2 x}{2 x-7}=-\frac{2 x-7+4}{2 x-7}=-1-\frac{4}{2 x-7} \Rightarrow \\ & \Rightarrow 7-2 x=\frac{4}{t^{2}+1} \Rightarrow x=-\frac{2}{t^{2}+1}+\frac{7}{2} \\ & d x=\fr...
\frac{\pi}{3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
45,999
## Problem Statement Calculate the definite integral: $$ \int_{0}^{7} \frac{\sqrt{x+25}}{(x+25)^{2} \sqrt{x+1}} d x $$
## Solution $$ \int_{0}^{7} \frac{\sqrt{x+25}}{(x+25)^{2} \sqrt{x+1}} d x=\int_{0}^{7} \frac{1}{(x+25) \sqrt{(x+25)(x+1)}} d x= $$ Substitution: $$ \begin{aligned} & t=\sqrt{\frac{x+25}{x+1}} \\ & d t=\frac{1}{2} \sqrt{\frac{x+1}{x+25}} \cdot \frac{1 \cdot(x+1)-(x+25) \cdot 1}{(x+1)^{2}} d x=\frac{1}{2} \sqrt{\frac{...
\frac{1}{40}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,000
## Problem Statement Calculate the definite integral: $$ \int_{0}^{2} \frac{(4 \sqrt{2-x}-\sqrt{3 x+2}) d x}{(\sqrt{3 x+2}+4 \sqrt{2-x})(3 x+2)^{2}} $$
## Solution Introduce the substitution: $$ t=\sqrt{\frac{2-x}{3 x+2}} $$ Then: $$ \begin{aligned} & x=\frac{2-2 t^{2}}{3 t^{2}+1}, \quad d x=-\frac{16 t}{\left(3 t^{2}+1\right)^{2}} d t \\ & \text { When } x=0, \quad t=1 \\ & \text { When } x=2, \quad t=0 \\ & 3 x+2=\frac{8}{3 t^{2}+1} \end{aligned} $$ We obtain: ...
\frac{1}{32}\ln5
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,001
## Problem Statement Calculate the definite integral: $$ \int_{0}^{2} e^{\sqrt{(2-x) /(2+x)}} \cdot \frac{d x}{(2+x) \sqrt{4-x^{2}}} $$
## Solution $$ \int_{0}^{2} e^{\sqrt{(2-x) /(2+x)}} \cdot \frac{d x}{(2+x) \sqrt{4-x^{2}}}= $$ Substitution: $$ \begin{aligned} & t=\sqrt{\frac{2-x}{2+x}} \\ & d t=\frac{1}{2} \cdot \sqrt{\frac{2+x}{2-x}} \cdot\left(\frac{2-x}{2+x}\right)^{\prime} \cdot d x=\frac{1}{2} \cdot \sqrt{\frac{2+x}{2-x}} \cdot \frac{-4}{(2...
\frac{e-1}{2}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,002
## Problem Statement Calculate the definite integral: $$ \int_{3}^{5} \sqrt{\frac{2-x}{x-6}} d x $$
## Solution $$ \int_{3}^{5} \sqrt{\frac{2-x}{x-6}} d x= $$ Substitution: $$ \begin{aligned} & t=\sqrt{\frac{2-x}{x-6}} \Rightarrow t^{2}=\frac{2-x}{x-6}=-\frac{x-6+4}{x-6}=-1-\frac{4}{x-6} \Rightarrow \\ & \Rightarrow 6-x=\frac{4}{t^{2}+1} \Rightarrow x=-\frac{4}{t^{2}+1}+6 \\ & d x=\frac{4}{\left(t^{2}+1\right)^{2}...
\frac{2\pi}{3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,003
## Problem Statement Calculate the definite integral: $$ \int_{1 / 24}^{1 / 3} \frac{5 \sqrt{x+1}}{(x+1)^{2} \sqrt{x}} d x $$
## Solution $$ \int_{1 / 24}^{1 / 3} \frac{5 \sqrt{x+1}}{(x+1)^{2} \sqrt{x}} d x=\int_{1 / 24}^{1 / 3} \frac{5}{(x+1) \sqrt{(x+1) x}} d x= $$ Substitution: $$ \begin{aligned} & t=\sqrt{\frac{x+1}{x}} \\ & d t=\frac{1}{2} \sqrt{\frac{x}{x+1}} \cdot \frac{1 \cdot x-(x+1) \cdot 1}{x^{2}} d x=\frac{1}{2} \sqrt{\frac{x}{...
3
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,004
## Problem Statement Calculate the definite integral: $$ \int_{9}^{15} \sqrt{\frac{6-x}{x-18}} d x $$
## Solution $$ \int_{9}^{15} \sqrt{\frac{6-x}{x-18}} d x= $$ Substitution: $$ \begin{aligned} & t=\sqrt{\frac{6-x}{x-18}} \Rightarrow t^{2}=\frac{6-x}{x-18}=-\frac{x-18+12}{x-18}=-1-\frac{12}{x-18} \Rightarrow \\ & \Rightarrow 18-x=\frac{12}{t^{2}+1} \Rightarrow x=-\frac{12}{t^{2}+1}+18 \\ & d x=\frac{12}{\left(t^{2...
2\pi
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,005
## Problem Statement Calculate the definite integral: $$ \int_{16 / 15}^{4 / 3} \frac{4 \sqrt{x}}{x^{2} \sqrt{x-1}} d x $$
## Solution ## Problem 11. ## Calculate the definite integral: $$ I=\int_{16 / 15}^{4 / 3} \frac{4 \sqrt{x}}{x^{2} \sqrt{x-1}} d x $$ ## Perform a variable substitution: $$ \begin{aligned} & t=\sqrt{\frac{x}{x-1}}, \text { hence } t^{2}=\frac{x}{x-1}, \text { that is } x=1+\frac{1}{t^{2}-1}, \text { and } \\ & d x...
2
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,008
## Problem Statement Calculate the definite integral: $$ \int_{0}^{6} \frac{e^{\sqrt{(6-x) /(6+x)}} \cdot d x}{(6+x) \sqrt{36-x^{2}}} $$
## Solution $$ \int_{0}^{6} \frac{e^{\sqrt{(6-x) /(6+x)}} \cdot d x}{(6+x) \sqrt{36-x^{2}}}=\int_{0}^{6} \frac{e^{\sqrt{(6-x) /(6+x)}} \cdot d x}{(6+x)^{2} \sqrt{\frac{6-x}{6+x}}}=-\left.\frac{1}{6} \cdot e^{\sqrt{\frac{6-x}{6+x}}}\right|_{0} ^{6}=\frac{e-1}{6} $$ Source — "http://pluspi.org/wiki/index.php/\�\�\�\�\�...
\frac{e-1}{6}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,009
## Problem Statement Calculate the definite integral: $$ \int_{1}^{64} \frac{6-\sqrt{x}+\sqrt[4]{x}}{\sqrt{x^{3}}-7 x-6 \sqrt[4]{x^{3}}} d x $$
## Solution $$ \int_{1}^{64} \frac{6-\sqrt{x}+\sqrt[4]{x}}{\sqrt{x^{3}}-7 x-6 \sqrt[4]{x^{3}}} d x= $$ Substitution: $$ \begin{aligned} & x=t^{4}, d x=4 t^{3} d t \\ & x=1 \Rightarrow t=\sqrt[4]{1}=1 \\ & x=64 \Rightarrow t=\sqrt[4]{64}=2 \sqrt{2} \end{aligned} $$ We get: $$ =\int_{1}^{2 \sqrt{2}} \frac{\left(6-t^...
4\ln(\frac{2}{2\sqrt{2}+1})
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,010
## Problem Statement Calculate the definite integral: $$ \int_{0}^{1} \frac{(4 \sqrt{1-x}-\sqrt{x+1}) d x}{(\sqrt{x+1}+4 \sqrt{1-x})(x+1)^{2}} $$
## Solution $$ \int_{0}^{1} \frac{(4 \sqrt{1-x}-\sqrt{x+1}) d x}{(\sqrt{x+1}+4 \sqrt{1-x})(x+1)^{2}}=\int_{0}^{1} \frac{\left(4 \sqrt{\frac{1-x}{x+1}}-1\right) d x}{\left(1+4 \sqrt{\frac{1-x}{x+1}}\right)(x+1)^{2}}= $$ Introduce the substitution: $$ t=\sqrt{\frac{1-x}{x+1}} $$ Then $$ \begin{aligned} & t^{2}=\frac...
\frac{1}{8}\ln5
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,011
## Problem Statement Calculate the definite integral: $$ \int_{0}^{3} \frac{e^{\sqrt{(3-x) /(3+x)}} d x}{(3+x) \sqrt{9-x^{2}}} $$
## Solution $$ \int_{0}^{3} \frac{e^{\sqrt{(3-x) /(3+x)}} d x}{(3+x) \sqrt{9-x^{2}}}= $$ Substitution: $$ \begin{aligned} & t=\sqrt{\frac{3-x}{3+x}} \\ & d t=\frac{1}{2} \cdot \sqrt{\frac{3+x}{3-x}} \cdot\left(\frac{3-x}{3+x}\right)^{\prime} \cdot d x=\frac{1}{2} \cdot \sqrt{\frac{3+x}{3-x}} \cdot \frac{-6}{(3+x)^{2...
\frac{e-1}{3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,012
## Problem Statement Calculate the definite integral: $$ \int_{0}^{2} \frac{(4 \sqrt{2-x}-\sqrt{x+2}) d x}{(\sqrt{x+2}+4 \sqrt{2-x})(x+2)^{2}} $$
## Solution $$ \int_{0}^{2} \frac{(4 \sqrt{2-x}-\sqrt{x+2}) d x}{(\sqrt{x+2}+4 \sqrt{2-x})(x+2)^{2}}=\int_{0}^{2} \frac{\left(4 \sqrt{\frac{2-x}{x+2}}-1\right) d x}{\left(1+4 \sqrt{\frac{2-x}{x+2}}\right)(x+2)^{2}}= $$ Introduce the substitution: $$ t=\sqrt{\frac{2-x}{x+2}} $$ Then $$ \begin{aligned} & t^{2}=\frac...
\frac{1}{4}\ln5
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,013
## Condition of the problem Prove that $\lim _{n \rightarrow \infty} a_{n}=a_{\text {(specify }} N(\varepsilon)$ ). $a_{n}=\frac{2-3 n^{2}}{4+5 n^{2}}, a=-\frac{3}{5}$
## Solution By the definition of the limit: $$ \begin{aligned} & \forall \varepsilon>0: \exists N(\varepsilon) \in \mathbb{N}: \forall n: n \geq N(\varepsilon):\left|a_{n}-a\right| \\ & \left|\frac{10-15 n^{2}+12+15 n^{2}}{5\left(4+5 n^{2}\right)}\right| \\ & \left.\frac{22}{5\left(4+5 n^{2}\right)} \right\rvert\, \\...
proof
Calculus
proof
Yes
Yes
olympiads
false
46,014
## Problem Statement Calculate the limit of the numerical sequence: $$ \lim _{n \rightarrow \infty} \frac{(n+2)^{2}-(n-2)^{2}}{(n+3)^{2}} $$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{(n+2)^{2}-(n-2)^{2}}{(n+3)^{2}}=\lim _{n \rightarrow \infty} \frac{n^{2}+4 n+4-n^{2}+4 n-4}{n^{2}+6 n+9}= \\ & =\lim _{n \rightarrow \infty} \frac{\frac{1}{n} 8 n}{\frac{1}{n}\left(n^{2}+6 n+9\right)}=\lim _{n \rightarrow \infty} \frac{8}{n+6+\frac{9}...
0
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,015
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty} \frac{\sqrt{n+1}-\sqrt[3]{n^{3}+1}}{\sqrt[4]{n+1}-\sqrt[5]{n^{5}+1}}$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{\sqrt{n+1}-\sqrt[3]{n^{3}+1}}{\sqrt[4]{n+1}-\sqrt[5]{n^{5}+1}}=\lim _{n \rightarrow \infty} \frac{\frac{1}{n}\left(\sqrt{n+1}-\sqrt[3]{n^{3}+1}\right)}{\frac{1}{n}\left(\sqrt[4]{n+1}-\sqrt[5]{n^{5}+1}\right)}= \\ & =\lim _{n \rightarrow \infty} \frac{...
1
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,016
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty} \sqrt{n(n+1)(n+2)}\left(\sqrt{n^{3}-3}-\sqrt{n^{3}-2}\right)$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \sqrt{n(n+1)(n+2)}\left(\sqrt{n^{3}-3}-\sqrt{n^{3}-2}\right)= \\ & =\lim _{n \rightarrow \infty} \frac{\sqrt{n(n+1)(n+2)}\left(\sqrt{n^{3}-3}-\sqrt{n^{3}-2}\right)\left(\sqrt{n^{3}-3}+\sqrt{n^{3}-2}\right)}{\sqrt{n^{3}-3}+\sqrt{n^{3}-2}}= \\ & =\lim _{n \ri...
-\frac{1}{2}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,017
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty}\left(\frac{n+5}{n-7}\right)^{\frac{n}{6}+1}$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty}\left(\frac{n+5}{n-7}\right)^{\frac{n}{6}+1}=\lim _{n \rightarrow \infty}\left(\frac{n-7+12}{n-7}\right)^{\frac{n}{6}+1}= \\ & =\lim _{n \rightarrow \infty}\left(1+\frac{12}{n-7}\right)^{\frac{n}{6}+1}=\lim _{n \rightarrow \infty}\left(1+\frac{1}{\left(\frac...
e^2
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,019
## Condition of the problem Prove that (find $\delta(\varepsilon)$ : $$ \lim _{x \rightarrow-\frac{1}{5}} \frac{15 x^{2}-2 x-1}{x+\frac{1}{5}}=-8 $$
## Solution According to the definition of the limit of a function by Cauchy: If a function \( f: M \subset \mathbb{R} \rightarrow \mathbb{R} \) and \( a \in M' \) is a limit point of the set \( M \). The number ![](https://cdn.mathpix.com/cropped/2024_05_22_08a731a792d2ab45f373g-04.jpg?height=82&width=1488&top_left...
proof
Calculus
proof
Yes
Yes
olympiads
false
46,020
## Condition of the problem Prove that the function $f(x)_{\text {is continuous at the point }} x_{0}$ (find $\delta(\varepsilon)$ ): $f(x)=4 x^{2}+6, x_{0}=7$
## Solution By definition, the function $f(x)_{\text {is continuous at the point }} x=x_{0}$, if $\forall \varepsilon>0: \exists \delta(\varepsilon)>0:$. $$ \left|x-x_{0}\right|0_{\text {there exists such }} \delta(\varepsilon)>0$, such that $\left|f(x)-f\left(x_{0}\right)\right|<\varepsilon$ when $\left|x-x_{0}\righ...
proof
Calculus
proof
Yes
Yes
olympiads
false
46,021
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow-3} \frac{x^{3}+7 x^{2}+15 x+9}{x^{3}+8 x^{2}+21 x+18}$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow-3} \frac{x^{3}+7 x^{2}+15 x+9}{x^{3}+8 x^{2}+21 x+18}=\left\{\frac{0}{0}\right\}=\lim _{x \rightarrow-3} \frac{(x+3)\left(x^{2}+4 x+3\right)}{(x+3)\left(x^{2}+5 x+6\right)}= \\ & =\lim _{x \rightarrow-3} \frac{x^{2}+4 x+3}{x^{2}+5 x+6}=\left\{\frac{0}{0}\right\}=\l...
2
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,022
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow-8} \frac{10-x-6 \sqrt{1-x}}{2+\sqrt[3]{x}} $$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow-8} \frac{10-x-6 \sqrt{1-x}}{2+\sqrt[3]{x}}=\lim _{x \rightarrow-8} \frac{(10-x-6 \sqrt{1-x})(10-x+6 \sqrt{1-x})}{(2+\sqrt[3]{x})}= \\ & =\lim _{x \rightarrow-8} \frac{(10-x+6 \sqrt{1-x})}{(2+\sqrt[3]{x})(10-x+6 \sqrt{1-x})}=\lim _{x \rightarrow-8} \frac{100-20 x+x^...
0
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,023
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 0} \frac{2\left(e^{\pi x}-1\right)}{3(\sqrt[3]{1+x}-1)} $$
## Solution We will use the substitution of equivalent infinitesimals: $e^{\pi x}-1 \sim \pi x$, as $x \rightarrow 0 (\pi x \rightarrow 0)$ We get: $$ \begin{aligned} & \lim _{x \rightarrow 0} \frac{2\left(e^{\pi x}-1\right)}{3(\sqrt[3]{1+x}-1)}=\left\{\frac{0}{0}\right\}=\lim _{x \rightarrow 0} \frac{2 \pi x\left(...
2\pi
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,024
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow \pi} \frac{\sin 5 x}{\tan 3 x}$
## Solution Substitution: $x=y+\pi \Rightarrow y=x-\pi$ $x \rightarrow \pi \Rightarrow y \rightarrow 0$ We get: $\lim _{x \rightarrow \pi} \frac{\sin 5 x}{\tan 3 x}=\lim _{y \rightarrow 0} \frac{\sin 5(y+\pi)}{\tan 3(y+\pi)}=$ $=\lim _{y \rightarrow 0} \frac{\sin (5 y+5 \pi)}{\tan(3 y+3 \pi)}=\lim _{y \rightarrow...
-\frac{5}{3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,025
Condition of the problem Calculate the limit of the function: $\lim _{x \rightarrow \pi} \frac{\operatorname{tg}\left(3^{\pi / x}-3\right)}{3^{\cos (3 x / 2)}-1}$
## Solution Substitution: $x=y+\pi \Rightarrow y=x-\pi$ $x \rightarrow \pi \Rightarrow y \rightarrow 0$ We get: $\lim _{x \rightarrow \pi} \frac{\operatorname{tg}\left(3^{\pi / x}-3\right)}{3^{\cos (3 x / 2)}-1}=\lim _{y \rightarrow 0} \frac{\operatorname{tg}\left(3^{\pi /(y+\pi)}-3\right)}{3^{\cos (3(y+\pi) / 2)}...
-\frac{2}{\pi}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,026
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0} \frac{2^{3 x}-3^{2 x}}{x+\arcsin x^{3}}$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow 0} \frac{2^{3 x}-3^{2 x}}{x+\arcsin x^{3}}=\lim _{x \rightarrow 0} \frac{\left(8^{x}-1\right)-\left(9^{x}-1\right)}{x+\arcsin x^{3}}= \\ & =\lim _{x \rightarrow 0} \frac{\left(\left(e^{\ln 8}\right)^{x}-1\right)-\left(\left(e^{\ln 9}\right)^{x}-1\right)}{x+\arcsin ...
\ln\frac{2^{3}}{3^{2}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,027
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 3} \frac{\log _{3} x-1}{\tan \pi x}$
## Solution $\lim _{x \rightarrow 3} \frac{\log _{3} x-1}{\tan \pi x}=\lim _{x \rightarrow 3} \frac{\log _{3} x-\log _{3} 3}{\tan \pi x}=$ $=\lim _{x \rightarrow 3} \frac{\log _{3} \frac{x}{3}}{\tan \pi x}=\lim _{x \rightarrow 3} \frac{\ln \frac{x}{3} / \ln 3}{\tan \pi x}=$ $=\lim _{x \rightarrow 3} \frac{\ln \frac{x...
\frac{1}{3\pi\ln3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,028
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0}\left(1-\sin ^{2} \frac{x}{2}\right)^{\frac{1}{\ln \left(1+\operatorname{tg}^{2} 3 x\right)}}$
## Solution $\lim _{x \rightarrow 0}\left(1-\sin ^{2} \frac{x}{2}\right)^{\frac{1}{\ln \left(1+\operatorname{tg}^{2} 3 x\right)}}=$ $=\lim _{x \rightarrow 0}\left(e^{\ln \left(1-\sin ^{2} \frac{x}{2}\right)}\right)^{\frac{1}{\ln \left(1+\operatorname{tg}^{2} 3 x\right)}}=$ $=\lim _{x \rightarrow 0} e^{\frac{\ln \lef...
e^{-\frac{1}{36}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,029
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0}\left(\frac{\arcsin ^{2} x}{\arcsin ^{2} 4 x}\right)^{2 x+1}$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow 0}\left(\frac{\arcsin ^{2} x}{\arcsin ^{2} 4 x}\right)^{2 x+1}=\left(\lim _{x \rightarrow 0} \frac{\arcsin ^{2} x}{\arcsin ^{2} 4 x}\right)^{\lim _{x \rightarrow 0} 2 x+1}= \\ & =\left(\lim _{x \rightarrow 0} \frac{\arcsin ^{2} x}{\arcsin ^{2} 4 x}\right)^{2 \cdot ...
\frac{1}{16}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,030
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow \pi}\left(\operatorname{ctg}\left(\frac{x}{4}\right)\right)^{1 / \cos \left(\frac{x}{2}\right)}$
## Solution Substitution: $$ \begin{aligned} & x=4 y+\pi \Rightarrow y=\frac{1}{4}(x-\pi) \\ & x \rightarrow \pi \Rightarrow y \rightarrow 0 \end{aligned} $$ We get: $$ \begin{aligned} & \lim _{x \rightarrow \pi}\left(\operatorname{ctg}\left(\frac{4 y+\pi}{4}\right)\right)^{1 / \cos \left(\frac{4 y+\pi}{2}\right)}=...
e
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,031
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 1}\left(\frac{1+\cos \pi x}{\tan^{2} \pi x}\right)^{x^{2}}$
## Solution $\lim _{x \rightarrow 1}\left(\frac{1+\cos \pi x}{\tan^{2} \pi x}\right)^{x^{2}}=\lim _{x \rightarrow 1}\left(\frac{1+1-2 \sin ^{2}\left(\frac{\pi x}{2}\right)}{\tan^{2} \pi x}\right)^{x^{2}}=$ $$ \begin{aligned} & =\lim _{x \rightarrow 1}\left(\frac{2-2 \sin ^{2}\left(\frac{\pi x}{2}\right)}{\tan^{2} \pi...
\frac{1}{2}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,032
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 1} \frac{\sin x+\sin (\pi x) \cdot \operatorname{arctg} \frac{1+x}{1-x}}{1+\cos x}$
## Solution Since $\operatorname{arctg} \frac{1+x}{1-x}_{\text {- is bounded, and }}$ $$ \begin{aligned} & \lim _{x \rightarrow 1} \sin (\pi x)=\sin (\pi \cdot 1)=\sin \pi=0 \\ & \sin (\pi x) \cdot \operatorname{arctg} \frac{1+x}{1-x} \rightarrow 0, \text { then } \\ & \text {, as } x \rightarrow 0 \end{aligned} $$ ...
\frac{\sin1}{1+\cos1}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,033
## Problem Statement Write the decomposition of vector $x$ in terms of vectors $p, q, r$: $x=\{3 ; 1 ; 8\}$ $p=\{0 ; 1 ; 3\}$ $q=\{1 ; 2 ;-1\}$ $r=\{2 ; 0 ;-1\}$
## Solution The desired decomposition of vector $x$ is: $x=\alpha \cdot p+\beta \cdot q+\gamma \cdot r$ Or in the form of a system: $$ \left\{\begin{array}{l} \alpha \cdot p_{1}+\beta \cdot q_{1}+\gamma \cdot r_{1}=x_{1} \\ \alpha \cdot p_{2}+\beta \cdot q_{2}+\gamma \cdot r_{2}=x_{2} \\ \alpha \cdot p_{3}+\beta \c...
3p-q+2r
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,034
## Problem Statement Are the vectors $c_{1 \text { and }} c_{2}$, constructed from vectors $a \text{ and } b$, collinear? $a=\{5 ; 0 ;-2\}$ $b=\{6 ; 4 ; 3\}$ $c_{1}=5 a-3 b$ $c_{2}=6 b-10 a$
## Solution Vectors are collinear if there exists a number $\gamma$ such that $c_{1}=\gamma \cdot c_{2}$. That is, vectors are collinear if their coordinates are proportional. It is not hard to notice that $c_{2}=-2(5 a-3 b)=-2 c_{1}$ for any $a$ and $b$. That is, $c_{1}=-2 \cdot c_{2}$, which means the vectors $c_{...
c_{1}=-2\cdotc_{2}
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,035
## Problem Statement Find the cosine of the angle between vectors $\overrightarrow{A B}$ and $\overrightarrow{A C}$. $A(0 ; 2 ; -4), B(8 ; 2 ; 2), C(6 ; 2 ; 4)$
## Solution Let's find $\overrightarrow{A B}$ and $\overrightarrow{A C}$: $\overrightarrow{A B}=(8-0 ; 2-2 ; 2-(-4))=(8 ; 0 ; 6)$ $\overrightarrow{A C}=(6-0 ; 2-2 ; 4-(-4))=(6 ; 0 ; 8)$ We find the cosine of the angle $\phi$ between the vectors $\overrightarrow{A B}$ and $\overrightarrow{A C}$: $\cos (\overrightarr...
0.96
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,036
## Task Condition Calculate the area of the parallelogram constructed on vectors $a$ and $b$. $a=5 p+q$ $b=p-3 q$ $|p|=1$ $|q|=2$ $(\widehat{p, q})=\frac{\pi}{3}$
## Solution The area of the parallelogram constructed on vectors $a$ and $b$ is numerically equal to the modulus of their vector product: $S=|a \times b|$ We compute $a \times b$ using the properties of the vector product: $a \times b=(5 p+q) \times(p-3 q)=5 \cdot p \times p+5 \cdot(-3) \cdot p \times q+q \times p-...
16\sqrt{3}
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,037
## Task Condition Are the vectors $a, b$ and $c$ coplanar? $a=\{-2 ;-4 ;-3\}$ $b=\{4 ; 3 ; 1\}$ $c=\{6 ; 7 ; 4\}$
## Solution For three vectors to be coplanar (lie in the same plane or parallel planes), it is necessary and sufficient that their scalar triple product $(a, b, c)$ be equal to zero. $$ \begin{aligned} & (a, b, c)=\left|\begin{array}{ccc} -2 & -4 & -3 \\ 4 & 3 & 1 \\ 6 & 7 & 4 \end{array}\right|= \\ & =-2 \cdot\left|...
proof
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,038
## Task Condition Calculate the volume of the tetrahedron with vertices at points $A_{1}, A_{2}, A_{3}, A_{4_{\text {and }}}$ its height dropped from vertex $A_{4 \text { to the face }} A_{1} A_{2} A_{3}$. $A_{1}(-3 ; 4 ;-7)$ $A_{2}(1 ; 5 ;-4)$ $A_{3}(-5 ;-2 ; 0)$ $A_{4}(2 ; 5 ; 4)$
## Solution From vertex $A_{1}$, we will draw vectors: $$ \begin{aligned} & \overrightarrow{A_{1} A_{2}}=\{1-(-3) ; 5-4 ;-4-(-7)\}=\{4 ; 1 ; 3\} \\ & \overrightarrow{A_{1} A_{3}}=\{-5-(-3) ;-2-4 ; 0-(-7)\}=\{-2 ;-6 ; 7\} \\ & \overrightarrow{A_{1} A_{4}}=\{2-(-3) ; 5-4 ; 4-(-7)\}=\{5 ; 1 ; 11\} \end{aligned} $$ Acco...
25\frac{1}{6}
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,039
## Problem Statement Find the distance from point $M_{0}$ to the plane passing through three points $M_{1}, M_{2}, M_{3}$. $M_{1}(-4 ; 2 ; 6)$ $M_{2}(2 ;-3 ; 0)$ $M_{3}(-10 ; 5 ; 8)$ $M_{0}(-12 ; 1 ; 8)$
## Solution Find the equation of the plane passing through three points $M_{1}, M_{2}, M_{3}$: $$ \left|\begin{array}{ccc} x-(-4) & y-2 & z-6 \\ 2-(-4) & -3-2 & 0-6 \\ -10-(-4) & 5-2 & 8-6 \end{array}\right|=0 $$ Perform transformations: $$ \begin{aligned} & \left|\begin{array}{ccc} x+4 & y-2 & z-6 \\ 6 & -5 & -6 \...
4
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,040
## Problem Statement Write the equation of the plane passing through point $A$ and perpendicular to vector $\overrightarrow{B C}$. $A(3, -3, -6)$ $B(1, 9, -5)$ $C(6, 6, -4)$
## Solution Let's find the vector $\overrightarrow{BC}:$ $\overrightarrow{BC}=\{6-1 ; 6-9 ;-4-(-5)\}=\{5 ;-3 ; 1\}$ Since the vector $\overrightarrow{BC}$ is perpendicular to the desired plane, it can be taken as the normal vector. Therefore, the equation of the plane will be: $5 \cdot(x-3)-3 \cdot(y-(-3))+(z-(-6))...
5x-3y+z-18=0
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,041
## Task Condition Find the angle between the planes: $x-3 y-2 z-8=0$ $x+y-z+3=0$
## Solution The dihedral angle between planes is equal to the angle between their normal vectors. The normal vectors of the given planes are: $\overrightarrow{n_{1}}=\{1 ;-3 ;-2\}$ $\overrightarrow{n_{2}}=\{1 ; 1 ;-1\}$ The angle $\phi$ between the planes is determined by the formula: $\cos \phi=\frac{\left(\overr...
\frac{\pi}{2}
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,042
## Problem Statement Find the coordinates of point $A$, which is equidistant from points $B$ and $C$. $A(0 ; y ; 0)$ $B(0 ;-4 ; 1)$ $C(1 ;-3 ; 5)$
## Solution Let's find the distances $A B$ and $A C$: $$ \begin{aligned} & A B=\sqrt{(0-0)^{2}+(-4-y)^{2}+(1-0)^{2}}=\sqrt{0+16+8 y+y^{2}+1}=\sqrt{y^{2}+8 y+17} \\ & A C=\sqrt{(1-0)^{2}+(-3-y)^{2}+(5-0)^{2}}=\sqrt{1+9+6 y+y^{2}+25}=\sqrt{y^{2}+6 y+35} \end{aligned} $$ Since by the condition of the problem $A B=A C$,...
A(0;9;0)
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,043
## problem statement Let $k$ be the coefficient of similarity transformation with the center at the origin. Is it true that point $A$ belongs to the image of plane $a$? $A(1 ; 1 ; 1)$ $a: 7 x-6 y+z-5=0$ $k=-2$
## Solution When transforming similarity with the center at the origin of the plane $a: A x+B y+C z+D=0$ and the coefficient $k$, the plane transitions to $a^{\prime}: A x+B y+C z+k \cdot D=0$. We find the image of the plane $a$: $a^{\prime}: 7 x-6 y+z+10=0$ Substitute the coordinates of point $A$ into the equatio...
12\neq0
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,044
## Task Condition Write the canonical equations of the line. $$ \begin{aligned} & 2 x-3 y+z+6=0 \\ & x-3 y-2 z+3=0 \end{aligned} $$
## Solution Canonical equations of a line: $$ \frac{x-x_{0}}{m}=\frac{y-y_{0}}{n}=\frac{z-z_{0}}{p} $$ where $\left(x_{0} ; y_{0} ; z_{0}\right)_{\text {- coordinates of some point on the line, and }} \vec{s}=\{m ; n ; p\}$ - its direction vector. Since the line belongs to both planes simultaneously, its direction ...
\frac{x+3}{9}=\frac{y}{5}=\frac{z}{-3}
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,045
## Problem Statement Find the point of intersection of the line and the plane. $\frac{x+3}{2}=\frac{y-1}{3}=\frac{z-1}{5}$ $2 x+3 y+7 z-52=0$
## Solution Let's write the parametric equations of the line. $$ \begin{aligned} & \frac{x+3}{2}=\frac{y-1}{3}=\frac{z-1}{5}=t \Rightarrow \\ & \left\{\begin{array}{l} x=-3+2 t \\ y=1+3 t \\ z=1+5 t \end{array}\right. \end{aligned} $$ Substitute into the equation of the plane: $$ \begin{aligned} & 2(-3+2 t)+3(1+3 t...
(-1;4;6)
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,046
## Problem Statement Find the point $M^{\prime}$ symmetric to the point $M$ with respect to the plane. $$ M(-1 ; 0 ;-1) $$ $2 x+6 y-2 z+11=0$
## Solution Let's find the equation of the line that is perpendicular to the given plane and passes through point $M$. Since the line is perpendicular to the given plane, we can take the normal vector of the plane as its direction vector: $\vec{s}=\vec{n}=\{2 ; 6 ;-2\}$ Then the equation of the desired line is: $\...
M^{\}(-2;-3;0)
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,047
## Task Condition Write the decomposition of vector $x$ in terms of vectors $p, q, r$: $x=\{6 ; 12 ;-1\}$ $p=\{1 ; 3 ; 0\}$ $q=\{2 ;-1 ; 1\}$ $r=\{0 ;-1 ; 2\}$
## Solution The desired decomposition of vector $x$ is: $x=\alpha \cdot p+\beta \cdot q+\gamma \cdot r$ Or in the form of a system: $$ \left\{\begin{array}{l} \alpha \cdot p_{1}+\beta \cdot q_{1}+\gamma \cdot r_{1}=x_{1} \\ \alpha \cdot p_{2}+\beta \cdot q_{2}+\gamma \cdot r_{2}=x_{2} \\ \alpha \cdot p_{3}+\beta \c...
4p+q-r
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,048
## Problem Statement Are the vectors $c_{1 \text { and }} c_{2}$, constructed from vectors $a \text{ and } b$, collinear? $a=\{1 ; 0 ; 1\}$ $b=\{-2 ; 3 ; 5\}$ $c_{1}=a+2 b$ $c_{2}=3 a-b$
## Solution Vectors are collinear if there exists a number $\gamma$ such that $c_{1}=\gamma \cdot c_{2}$. That is, vectors are collinear if their coordinates are proportional. We find: $$ \begin{aligned} & c_{1}=a+2 b=\{1+2 \cdot(-2) ; 0+2 \cdot 3 ; 1+2 \cdot 5\}=\{-3 ; 6 ; 11\} \\ & c_{2}=3 a-b=\{3 \cdot 1-(-2) ; 3...
proof
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,049
## Problem Statement Find the cosine of the angle between vectors $\overrightarrow{A B}$ and $\overrightarrow{A C}$. $$ A(0 ;-3 ; 6), B(-12 ;-3 ;-3), C(-9 ;-3 ;-6) $$
## Solution Let's find $\overrightarrow{A B}$ and $\overrightarrow{A C}$: $$ \begin{aligned} & \overrightarrow{A B}=(-12-0 ;-3-(-3) ;-3-6)=(-12 ; 0 ;-9) \\ & \overrightarrow{A C}=(-9-0 ;-3-(-3) ;-6-6)=(-9 ; 0 ;-12) \end{aligned} $$ We find the cosine of the angle $\phi$ between the vectors $\overrightarrow{A B}$ and...
0.96
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,050
## Task Condition Calculate the area of the parallelogram constructed on vectors $a$ and $b$. $a=3 p+q$ $b=p-2 q$ $|p|=4$ $|q|=1$ $\widehat{(\widehat{p}, q})=\frac{\pi}{4}$
## Solution The area of the parallelogram constructed on vectors $a$ and $b$ is numerically equal to the modulus of their vector product: $S=|a \times b|$ We compute $a \times b$ using the properties of the vector product: $$ \begin{aligned} & a \times b=(3 p+q) \times(p-2 q)=3 \cdot p \times p+3 \cdot(-2) \cdot p ...
14\sqrt{2}
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,051
## problem statement Are the vectors $a, b$ and $c$ coplanar? $a=\{3 ; 2 ; 1\}$ $b=\{2 ; 3 ; 4\}$ $c=\{3 ; 1 ;-1\}$
## Solution For three vectors to be coplanar (lie in the same plane or parallel planes), it is necessary and sufficient that their scalar triple product $(a, b, c)$ be equal to zero. $$ \begin{aligned} & (a, b, c)=\left|\begin{array}{ccc} 3 & 2 & 1 \\ 2 & 3 & 4 \\ 3 & 1 & -1 \end{array}\right|= \\ & =3 \cdot\left|\be...
proof
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,052
## problem statement Calculate the volume of the tetrahedron with vertices at points $A_{1}, A_{2}, A_{3}, A_{4_{\text {and }}}$ its height dropped from vertex $A_{4 \text { to the face }} A_{1} A_{2} A_{3}$. $A_{1}(-4 ; 2 ; 6)$ $A_{2}(2 ;-3 ; 0)$ $A_{3}(-10 ; 5 ; 8)$ $A_{4}(-5 ; 2 ;-4)$
## Solution From vertex $A_{1 \text {, we draw vectors: }}$ $$ \begin{aligned} & \overrightarrow{A_{1} A_{2}}=\{2-(-4) ;-3-2 ; 0-6\}=\{6 ;-5 ;-6\} \\ & \vec{A}_{1} A_{3}=\{-10-(-4) ; 5-2 ; 8-6\}=\{-6 ; 3 ; 2\} \\ & \overrightarrow{A_{1} A_{4}}=\{-5-(-4) ; 2-2 ;-4-6\}=\{-1 ; 0 ;-10\} \end{aligned} $$ According to the...
18\frac{2}{3}
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,053
## problem statement Find the distance from the point $M_{0}$ to the plane passing through three points $M_{1}, M_{2}, M_{3}$. $M_{1}(-1 ; 2 ;-3)$ $M_{2}(4 ;-1 ; 0)$ $M_{3}(2 ; 1 ;-2)$ $M_{0}(1 ;-6 ;-5)$
## Solution Find the equation of the plane passing through three points $M_{1}, M_{2}, M_{3}$: $$ \left|\begin{array}{ccc} x-(-1) & y-2 & z-(-3) \\ 4-(-1) & -1-2 & 0-(-3) \\ 2-(-1) & 1-2 & -2-(-3) \end{array}\right|=0 $$ Perform transformations: $$ \begin{aligned} & \left|\begin{array}{ccc} x+1 & y-2 & z+3 \\ 5 & -...
5\sqrt{2}
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,054
## Problem Statement Write the equation of the plane passing through point $A$ and perpendicular to vector $\overrightarrow{B C}$. $A(-1 ; 3 ; 4)$ $B(-1 ; 5 ; 0)$ $C(2 ; 6 ; 1)$
## Solution Let's find the vector $\overrightarrow{BC}:$ $\overrightarrow{BC}=\{2-(-1) ; 6-5 ; 1-0\}=\{3 ; 1 ; 1\}$ Since the vector $\overrightarrow{BC}$ is perpendicular to the desired plane, it can be taken as the normal vector. Therefore, the equation of the plane will be: $3 \cdot(x-(-1))+(y-3)+(z-4)=0$ $3 x+3...
3x+y+z-4=0
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,055
## Problem Statement Find the angle between the planes: $x-3 y+z-1=0$ $x+z-1=0$
## Solution The dihedral angle between planes is equal to the angle between their normal vectors. The normal vectors of the given planes are: $\overrightarrow{n_{1}}=\{1 ;-3 ; 1\}$ $\overrightarrow{n_{2}}=\{1 ; 0 ; 1\}$ The angle $\phi_{\text {between the planes is determined by }}$ the formula: $$ \begin{aligned}...
\arccos\sqrt{\frac{2}{11}}\approx6445^{\}38^{\\}
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,056
## Problem Statement Find the coordinates of point $A$, which is equidistant from points $B$ and $C$. $A(0 ; 0 ; z)$ $B(3 ; 3 ; 1)$ $C(4 ; 1 ; 2)$
## Solution Let's find the distances $A B$ and $A C$: $$ \begin{aligned} & A B=\sqrt{(3-0)^{2}+(3-0)^{2}+(1-z)^{2}}=\sqrt{9+9+1-2 z+z^{2}}=\sqrt{z^{2}-2 z+19} \\ & A C=\sqrt{(4-0)^{2}+(1-0)^{2}+(2-z)^{2}}=\sqrt{16+1+4-4 z+z^{2}}=\sqrt{z^{2}-4 z+21} \end{aligned} $$ Since according to the problem's condition $A B=A C...
A(0;0;1)
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,057
## Problem Statement Let $k$ be the coefficient of similarity transformation with the center at the origin. Is it true that point $A$ belongs to the image of plane $a?$ $A(2 ; 1 ; 2)$ $a: x-2 y+z+1=0$ $k=-2$
## Solution When transforming similarity with the center at the origin of the plane $a: A x+B y+C z+D=0_{\text{and coefficient }} k$ transitions to the plane $a^{\prime}: A x+B y+C z+k \cdot D=0$. We find the image of the plane $a$: $a^{\prime}: x-2 y+z-2=0$ Substitute the coordinates of point $A$ into the equatio...
0
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,058
## Task Condition Write the canonical equations of the line. $x-3 y+2 z+2=0$ $x+3 y+z+14=0$
## Solution Canonical equations of a line: $\frac{x-x_{0}}{m}=\frac{y-y_{0}}{n}=\frac{z-z_{0}}{p}$ where $\left(x_{0} ; y_{0} ; z_{0}\right)_{\text {- coordinates of some point on the line, and }} \vec{s}=\{m ; n ; p\}$ - its direction vector. Since the line belongs to both planes simultaneously, its direction vecto...
\frac{x+8}{-9}=\frac{y+2}{1}=\frac{z}{6}
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,059
## Problem Statement Find the point of intersection of the line and the plane. $\frac{x+1}{3}=\frac{y-3}{-4}=\frac{z+1}{5}$ $x+2 y-5 z+20=0$
## Solution Let's write the parametric equations of the line. $$ \begin{aligned} & \frac{x+1}{3}=\frac{y-3}{-4}=\frac{z+1}{5}=t \Rightarrow \\ & \left\{\begin{array}{l} x=-1+3 t \\ y=3-4 t \\ z=-1+5 t \end{array}\right. \end{aligned} $$ Substitute into the equation of the plane: $(-1+3 t)+2(3-4 t)-5(-1+5 t)+20=0$ ...
(2,-1,4)
Algebra
math-word-problem
Yes
Yes
olympiads
false
46,060
## Task Condition Find the point $M^{\prime}$ symmetric to the point $M$ with respect to the line. $M(2, -1, 1)$ $$ \frac{x-4.5}{1}=\frac{y+3}{-0.5}=\frac{z-2}{1} $$
## Solution We find the equation of the plane that is perpendicular to the given line and passes through point $M$. Since the plane is perpendicular to the given line, we can use the direction vector of the line as its normal vector: $\vec{n}=\vec{s}=\{1 ;-0.5 ; 1\}$ Then the equation of the desired plane is: $1 \c...
M^{\}(3;-3;-1)
Geometry
math-word-problem
Yes
Yes
olympiads
false
46,061
## Problem Statement Based on the definition of the derivative, find $f^{\prime}(0)$: $$ f(x)=\left\{\begin{array}{c} \sin \left(x \sin \frac{3}{x}\right), x \neq 0 \\ 0, x=0 \end{array}\right. $$
## Solution By definition, the derivative at the point $x=0$: $$ f^{\prime}(0)=\lim _{\Delta x \rightarrow 0} \frac{f(0+\Delta x)-f(0)}{\Delta x} $$ Based on the definition, we find: $$ \begin{aligned} & f^{\prime}(0)=\lim _{\Delta x \rightarrow 0} \frac{f(0+\Delta x)-f(0)}{\Delta x}=\lim _{\Delta x \rightarrow 0} ...
f^{\}(0)
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,062
## Task Condition Derive the equation of the normal to the given curve at the point with abscissa $x_{0}$. $y=x+\sqrt{x^{3}}, x_{0}=1$
## Solution Let's find $y^{\prime}:$ $$ y^{\prime}=\left(x+\sqrt{x^{3}}\right)^{\prime}=\left(x+x^{\frac{3}{2}}\right)^{\prime}=1+\frac{3}{2} \cdot x^{\frac{1}{2}}=1+\frac{3}{2} \sqrt{x} $$ Then: $y_{0}^{\prime}=y^{\prime}\left(x_{0}\right)=1+\frac{3}{2} \sqrt{x_{0}}=1+\frac{3}{2} \sqrt{1}=1+\frac{3}{2}=\frac{5}{2}...
-\frac{2x}{5}+2\frac{2}{5}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,063
## Condition of the problem Find the differential $d y$. $$ y=\arccos \left(\frac{1}{\sqrt{1+2 x^{2}}}\right), x>0 $$
## Solution $$ \begin{aligned} & d y=y^{\prime} \cdot d x=\left(\arccos \left(\frac{1}{\sqrt{1+2 x^{2}}}\right)\right)^{\prime} d x= \\ & =\left(\frac{-1}{\sqrt{1-\left(\frac{1}{\sqrt{1+2 x^{2}}}\right)^{2}}}\right) \cdot\left(\frac{1}{\sqrt{1+2 x^{2}}}\right)^{\prime} d x= \\ & =\left(\frac{-1}{\sqrt{1-\frac{1}{1+2 x...
\frac{\sqrt{2}\cdotx}{1+2x^{2}}\cdot
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,064
## Task Condition Approximately calculate using the differential. $y=\arcsin x, x=0.08$
## Solution If the increment $\Delta x = x - x_{0 \text{ of the argument }} x$ is small in absolute value, then $f(x) = f\left(x_{0} + \Delta x\right) \approx f\left(x_{0}\right) + f^{\prime}\left(x_{0}\right) \cdot \Delta x$ Choose: $x_{0} = 0$ Then: $\Delta x = 0.08$ Calculate: $y(0) = \arcsin 0 = 0$ $y^{\pr...
0.08
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,065
## Task Condition Find the derivative. $$ y=\frac{\left(1+x^{8}\right) \sqrt{1+x^{8}}}{12 x^{12}} $$
## Solution ## Method 1 $$ \begin{aligned} & y^{\prime}=\left(\frac{\left(1+x^{8}\right) \sqrt{1+x^{8}}}{12 x^{12}}\right)^{\prime}= \\ & =\frac{\left(8 x^{7} \cdot \sqrt{1+x^{8}}+\left(1+x^{8}\right) \cdot \frac{1}{2 \sqrt{1+x^{8}}} \cdot 8 x^{7}\right) \cdot x^{12}-\left(1+x^{8}\right) \sqrt{1+x^{8}} \cdot 12 x^{11...
\sqrt{e^{x}+1}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,066
## Task Condition Find the derivative. $$ y=\ln (\sqrt{x}+\sqrt{x+1}) $$
## Solution $$ \begin{aligned} & y^{\prime}=(\ln (\sqrt{x}+\sqrt{x+1}))^{\prime}=\frac{1}{\sqrt{x}+\sqrt{x+1}} \cdot\left(\frac{1}{2 \sqrt{x}}+\frac{1}{2 \sqrt{x+1}}\right)= \\ & =\frac{1}{\sqrt{x}+\sqrt{x+1}} \cdot \frac{\sqrt{x+1}+\sqrt{x}}{2 \sqrt{x} \cdot \sqrt{x+1}}=\frac{1}{2 \sqrt{x^{2}+x}} \end{aligned} $$ ##...
\frac{1}{2\sqrt{x^{2}+x}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,067
## Task Condition Find the derivative. $y=\arccos \frac{x^{2}-4}{\sqrt{x^{4}+16}}$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\arccos \frac{x^{2}-4}{\sqrt{x^{4}+16}}\right)^{\prime}=\frac{-1}{\sqrt{1-\left(\frac{x^{2}-4}{\sqrt{x^{4}+16}}\right)^{2}}} \cdot\left(\frac{x^{2}-4}{\sqrt{x^{4}+16}}\right)^{\prime}= \\ & =\frac{-\sqrt{x^{4}+16}}{\sqrt{x^{4}+16-\left(x^{2}-4\right)^{2}}} \cdot \frac{...
-\frac{2\sqrt{2}(4+x^{2})}{x^{4}+16}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,068
## Problem Statement Find the derivative. $y=\frac{1}{2} \operatorname{th} x+\frac{1}{4 \sqrt{2}} \ln \frac{1+\sqrt{2} \operatorname{th} x}{1-\sqrt{2} \operatorname{th} x}$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\frac{1}{2} \tanh x+\frac{1}{4 \sqrt{2}} \ln \frac{1+\sqrt{2} \tanh x}{1-\sqrt{2} \tanh x}\right)^{\prime}= \\ & =\frac{1}{2} \cdot \frac{1}{\cosh^{2} x}+\frac{1}{4 \sqrt{2}} \cdot \frac{1-\sqrt{2} \tanh x}{1+\sqrt{2} \tanh x} \cdot\left(\frac{1+\sqrt{2} \tanh x}{1-\sq...
\frac{1}{\cosh^{2}x(1-\sinh^{2}x)}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,069
Condition of the problem Find the derivative. $y=(\ln x)^{3^{x}}$
## Solution $y=(\ln x)^{3^{x}}$ $\ln y=3^{x} \cdot \ln (\ln x)$ $\frac{y^{\prime}}{y}=\left(3^{x} \cdot \ln (\ln x)\right)^{\prime}=3^{x} \cdot \ln 3 \cdot \ln (\ln x)+3^{x} \cdot \frac{1}{\ln x} \cdot \frac{1}{x}=$ $=3^{x} \cdot\left(\ln 3 \cdot \ln (\ln x)+\frac{1}{x \cdot \ln x}\right)$ $y^{\prime}=y \cdot 3^{x...
(\lnx)^{3^{x}}\cdot3^{x}\cdot(\ln3\cdot\ln(\lnx)+\frac{1}{x\cdot\lnx})
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,070
## Problem Statement Find the derivative. $$ y=\frac{2}{x-1} \cdot \sqrt{2 x-x^{2}}+\ln \frac{1+\sqrt{2 x-x^{2}}}{x-1} $$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\frac{2}{x-1} \cdot \sqrt{2 x-x^{2}}+\ln \frac{1+\sqrt{2 x-x^{2}}}{x-1}\right)^{\prime}= \\ & =\frac{\frac{2}{2 \sqrt{2 x-x^{2}}} \cdot(2-2 x)-2 \sqrt{2 x-x^{2}} \cdot 1}{(x-1)^{2}}+\frac{x-1}{1+\sqrt{2 x-x^{2}}} \cdot\left(\frac{1+\sqrt{2 x-x^{2}}}{x-1}\right)^{\prime...
\frac{2x^{2}-7x+3}{(x-1)^{2}\sqrt{2x-x^{2}}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,071
## Task Condition Find the derivative. $$ y=3 \arcsin \frac{3}{4 x+1}+2 \sqrt{4 x^{2}+2 x-2}, 4 x+1>0 $$
## Solution $$ y^{\prime}=\left(3 \arcsin \frac{3}{4 x+1}+2 \sqrt{4 x^{2}+2 x-2}\right)^{\prime}= $$ $$ \begin{aligned} & =\frac{3}{\sqrt{1-\left(\frac{3}{4 x+1}\right)^{2}}}+\frac{2}{2 \sqrt{4 x^{2}+2 x-2}} \cdot(8 x+2)= \\ & =\frac{3(4 x+1)}{\sqrt{(4 x+1)^{2}-3^{2}}}+\frac{8 x+2}{\sqrt{4 x^{2}+2 x-2}}=\frac{3(4 x+1...
\frac{7\cdot(4x+1)}{2\sqrt{4x^{2}+2x-2}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,072
## Problem Statement Find the derivative. $$ y=3 \frac{\sin x}{\cos ^{2} x}+2 \frac{\sin x}{\cos ^{4} x} $$
## Solution $$ \begin{aligned} & y^{\prime}=3 \frac{\cos ^{3} x-\sin x \cdot 2 \cos x \cdot(-\sin x)}{\cos ^{4} x}+2 \frac{\cos ^{5} x-\sin x \cdot 4 \cos ^{3} x \cdot(-\sin x)}{\cos ^{8} x}= \\ & =3 \frac{\cos ^{2} x+2 \sin ^{2} x}{\cos ^{3} x}+2 \frac{\cos ^{2} x+4 \sin ^{2} x}{\cos ^{5} x}=3 \frac{1-\sin ^{2} x+2 \...
\frac{3+3\sin^{2}x}{\cos^{3}x}+\frac{2-6\sin^{2}x}{\cos^{5}x}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,073
## Problem Statement Find the derivative $y_{x}^{\prime}$. $$ \left\{\begin{array}{l} x=\ln \left(t+\sqrt{t^{2}+1}\right) \\ y=t \sqrt{t^{2}+1} \end{array}\right. $$
## Solution $$ \begin{aligned} & x_{t}^{\prime}=\left(\ln \left(t+\sqrt{t^{2}+1}\right)\right)^{\prime}=\frac{1}{t+\sqrt{t^{2}+1}} \cdot\left(1+\frac{1}{2 \sqrt{t^{2}+1}} \cdot 2 t\right)= \\ & =\frac{1}{t+\sqrt{t^{2}+1}} \cdot\left(1+\frac{t}{\sqrt{t^{2}+1}}\right)=\frac{1}{t+\sqrt{t^{2}+1}} \cdot \frac{\sqrt{t^{2}+1...
2^{2}+1
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,074
## Problem Statement Derive the equations of the tangent and normal lines to the curve at the point corresponding to the parameter value $t=t_{0}$. \[ \left\{\begin{array}{l} x=\frac{2 t+t^{2}}{1+t^{3}} \\ y=\frac{2 t-t^{2}}{1+t^{3}} \end{array}\right. \] $t_{0}=1$
## Solution Since $t_{0}=1$, then $x_{0}=\frac{2 \cdot 1+1^{2}}{1+1^{3}}=\frac{3}{2}$ $y_{0}=\frac{2 \cdot 1-1^{2}}{1+1^{3}}=\frac{1}{2}$ Let's find the derivatives: $$ \begin{aligned} & x_{t}^{\prime}=\left(\frac{2 t+t^{2}}{1+t^{3}}\right)^{\prime}=\frac{(2+2 t) \cdot\left(1+t^{3}\right)-\left(2 t+t^{2}\right) \c...
3x-4-\frac{x}{3}+1
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,075
## Task Condition Find the $n$-th order derivative. $$ y=\lg (5 x+2) $$
## Solution $y^{\prime}=\frac{1}{(5 x+2) \cdot \ln 10} \cdot 5=\frac{5}{(5 x+2) \cdot \ln 10}$ $y^{\prime \prime}=\left(y^{\prime}\right)^{\prime}=\left(\frac{5}{(5 x+2) \cdot \ln 10}\right)^{\prime}=\frac{5}{\ln 10} \cdot\left(-\frac{1}{(5 x+2)^{2}} \cdot 5\right)=$ $=-\frac{5^{2}}{\ln 10} \cdot \frac{1}{(5 x+2)^{2...
y^{(n)}=\frac{(-1)^{n-1}\cdot(n-1)!\cdot5^{n}}{\ln10\cdot(5x+2)^{n}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,076
## Task Condition Find the derivative of the specified order. $$ y=\frac{\log _{2} x}{x^{3}}, y^{\prime \prime \prime}=? $$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\frac{\log _{2} x}{x^{3}}\right)^{\prime}=\left(\frac{\ln x}{\ln 2 \cdot x^{3}}\right)^{\prime}=\frac{\frac{1}{x} \cdot x^{3}-\ln x \cdot 3 x^{2}}{\ln 2 \cdot x^{6}}= \\ & =\frac{1-3 \ln x}{\ln 2 \cdot x^{4}} \\ & y^{\prime \prime}=\left(y^{\prime}\right)^{\prime}=\lef...
\frac{47-60\lnx}{\ln2\cdotx^{6}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,077
## Problem Statement Find the second-order derivative $y_{x x}^{\prime \prime}$ of the function given parametrically. $$ \left\{\begin{array}{l} x=t+\sin t \\ y=2-\cos t \end{array}\right. $$
## Solution $y_{x}^{\prime}=\frac{y^{\prime}(t)}{x^{\prime}(t)}$ $y_{x^{2}}^{\prime \prime}=\frac{\left(y_{x}^{\prime}\right)_{t}^{\prime}}{x^{\prime}(t)}$ $y^{\prime}(t)=\sin t$. $x^{\prime}(t)=1+\cos t$. $y_{x}^{\prime}=\frac{\sin t}{1+\cos t}$ $y_{x^{2}}^{\prime \prime}=\left(\frac{\sin t}{1+\cos t}\right)^{\p...
\frac{1}{(1+\cos)^{2}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,078
## Problem Statement Show that the function $y_{\text {satisfies equation (1). }}$. $y=x \cdot \sqrt{1-x^{2}}$ $y \cdot y^{\prime}=x-2 x^{3}$
## Solution $$ \begin{aligned} & y^{\prime}=\left(x \cdot \sqrt{1-x^{2}}\right)^{\prime}=\sqrt{1-x^{2}}+x \cdot \frac{1}{2 \sqrt{1-x^{2}}} \cdot(-2 x)= \\ & =\sqrt{1-x^{2}}-\frac{x^{2}}{\sqrt{1-x^{2}}} \end{aligned} $$ Substitute into equation (1): $$ x \cdot \sqrt{1-x^{2}} \cdot\left(\sqrt{1-x^{2}}-\frac{x^{2}}{\sq...
proof
Calculus
proof
Yes
Yes
olympiads
false
46,079
## Task Condition Based on the definition of the derivative, find $f^{\prime}(0)$ : $$ f(x)=\left\{\begin{array}{c} \sin x \cdot \cos \frac{5}{x}, x \neq 0 \\ 0, x=0 \end{array}\right. $$
## Solution By definition, the derivative at the point $x=0$: $f^{\prime}(0)=\lim _{\Delta x \rightarrow 0} \frac{f(0+\Delta x)-f(0)}{\Delta x}$ Based on the definition, we find: $$ \begin{aligned} & f^{\prime}(0)=\lim _{\Delta x \rightarrow 0} \frac{f(0+\Delta x)-f(0)}{\Delta x}=\lim _{\Delta x \rightarrow 0} \fra...
f^{\}(0)
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,080
## Task Condition Compose the equation of the normal to the given curve at the point with abscissa $x_{0}$. $y=\frac{x^{2}-3 x+6}{x^{2}}, x_{0}=3$
## Solution Let's find $y^{\prime}:$ $$ y^{\prime}=\left(\frac{x^{2}-3 x+6}{x^{2}}\right)^{\prime}=\left(1-\frac{3}{x}+\frac{6}{x^{2}}\right)^{\prime}=\frac{3}{x^{2}}-2 \cdot \frac{6}{x^{3}}=\frac{3}{x^{2}}-\frac{12}{x^{3}} $$ Then: $y_{0}^{\prime}=y^{\prime}\left(x_{0}\right)=\frac{3}{x_{0}^{2}}-\frac{12}{x_{0}^{3...
9x-26\frac{1}{3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,081
## Condition of the problem Find the differential $d y$. $$ y=\ln \left(x+\sqrt{1+x^{2}}\right)-\sqrt{1+x^{2}} \operatorname{arctg} x $$
## Solution $$ \begin{aligned} & d y=y^{\prime} \cdot d x=\left(\ln \left(x+\sqrt{1+x^{2}}\right)-\sqrt{1+x^{2}} \operatorname{arctg} x\right)^{\prime} d x= \\ & =\left(\frac{1}{x+\sqrt{1+x^{2}}} \cdot\left(1+\frac{1}{2 \sqrt{1+x^{2}}} \cdot 2 x\right)-\left(\frac{1}{2 \sqrt{1+x^{2}}} \cdot 2 x \cdot \operatorname{arc...
-\frac{1}{\sqrt{1+x^{2}}}\cdot\operatorname{arctg}x\cdot
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,082
## Task Condition Approximately calculate using the differential. $$ y=\sqrt[3]{x}, x=1,21 $$
## Solution If the increment $\Delta x = x - x_{\text{argument}}: x$ is small in absolute value, then $$ f(x) = f\left(x_{0} + \Delta x\right) \approx f\left(x_{0}\right) + f^{\prime}\left(x_{0}\right) \cdot \Delta x $$ Choose: $x_{0} = 1$ Then: $\Delta x = 0.21$ ## Calculation: $$ y(1) = \sqrt[3]{1} = 1 $$ $y...
1.07
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,083
## Task Condition Find the derivative. $y=\ln \operatorname{tg}\left(\frac{\pi}{4}+\frac{x}{2}\right)$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\ln \tan\left(\frac{\pi}{4}+\frac{x}{2}\right)\right)^{\prime}=\frac{1}{\tan\left(\frac{\pi}{4}+\frac{x}{2}\right)} \cdot \frac{1}{\cos ^{2}\left(\frac{\pi}{4}+\frac{x}{2}\right)} \cdot \frac{1}{2}= \\ & =\frac{1}{2 \sin \left(\frac{\pi}{4}+\frac{x}{2}\right) \cdot \co...
\frac{1}{\cosx}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,086
## Task Condition Find the derivative. $$ y=\sqrt[3]{\operatorname{ctg} 2}-\frac{1}{20} \cdot \frac{\cos ^{2} 10 x}{\sin 20 x} $$
## Solution $y^{\prime}=\left(\sqrt[3]{\operatorname{ctg} 2}-\frac{1}{20} \cdot \frac{\cos ^{2} 10 x}{\sin 20 x}\right)^{\prime}=0-\frac{1}{20} \cdot\left(\frac{\cos ^{2} 10 x}{\sin 20 x}\right)^{\prime}=$ $=-\frac{1}{20} \cdot\left(\frac{\cos ^{2} 10 x}{2 \sin 10 x \cdot \cos 10 x}\right)^{\prime}=-\frac{1}{40} \cdo...
\frac{1}{4\sin^{2}10x}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,087
## Problem Statement Find the derivative. $$ y=\frac{x^{3}}{3} \cdot \arccos x-\frac{2+x^{2}}{9} \cdot \sqrt{1-x^{2}} $$
## Solution $y^{\prime}=\left(\frac{x^{3}}{3} \cdot \arccos x-\frac{2+x^{2}}{9} \cdot \sqrt{1-x^{2}}\right)^{\prime}=$ $=x^{2} \cdot \arccos x+\frac{x^{3}}{3} \cdot \frac{-1}{\sqrt{1-x^{2}}}-\frac{2 x}{9} \cdot \sqrt{1-x^{2}}-\frac{2+x^{2}}{9} \cdot \frac{1}{2 \sqrt{1-x^{2}}} \cdot(-2 x)=$ $=x^{2} \cdot \arccos x-\fra...
x^{2}\cdot\arccosx
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,088
## problem statement Find the derivative. $$ y=\frac{1}{6} \ln \frac{1-\operatorname{sh} 2 x}{2+\operatorname{sh} 2 x} $$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\frac{1}{6} \ln \frac{1-\operatorname{sh} 2 x}{2+\operatorname{sh} 2 x}\right)^{\prime}= \\ & =\frac{1}{6} \cdot \frac{2+\operatorname{sh} 2 x}{1-\operatorname{sh} 2 x} \cdot \frac{-\operatorname{ch} 2 x \cdot 2 \cdot(2+\operatorname{sh} 2 x)-(1-\operatorname{sh} 2 x) ...
\frac{\operatorname{ch}2x}{\operatorname{sh}^{2}2x+\operatorname{sh}2x-2}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,089
## Task Condition Find the derivative. $$ y=(\cos 5 x)^{e^{x}} $$
## Solution $$ \begin{aligned} & y=(\cos 5 x')^{e^{e^{x}}} \\ & \ln y=e^{x} \cdot \ln (\cos 5 x) \\ & \frac{y'}{y}=e^{x} \cdot \ln (\cos 5 x)+e^{x} \cdot \frac{1}{\cos 5 x} \cdot(-\sin 5 x)= \\ & =e^{x} \cdot \ln (\cos 5 x)-e^{x} \cdot \tan 5 x=e^{x} \cdot(\ln (\cos 5 x)-\tan 5 x) \\ & y'=y \cdot e^{x} \cdot(\ln (\cos...
(\cos5x)^{e^{x}}\cdote^{x}\cdot(\ln(\cos5x)-\tan5x)
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,090
## Problem Statement Find the derivative. $$ y=\ln \frac{1+2 \sqrt{-x-x^{2}}}{2 x+1}+\frac{4}{2 x+1} \sqrt{-x-x^{2}} $$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\ln \frac{1+2 \sqrt{-x-x^{2}}}{2 x+1}+\frac{4}{2 x+1} \sqrt{-x-x^{2}}\right)^{\prime}= \\ & =\frac{2 x+1}{1+2 \sqrt{-x-x^{2}}} \cdot \frac{\frac{1}{\sqrt{-x-x^{2}}} \cdot(-1-2 x) \cdot(2 x+1)-\left(1+2 \sqrt{-x-x^{2}}\right) \cdot 2}{(2 x+1)^{2}}+ \\ & +\frac{4 \cdot \...
-\frac{2x+3}{\sqrt{-x-x^{2}}\cdot(2x+1)^{2}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,091
## Problem Statement Find the derivative. $$ y=\sqrt{1-3 x-2 x^{2}}+\frac{3}{2 \sqrt{2}} \arcsin \frac{4 x+3}{\sqrt{17}} $$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\sqrt{1-3 x-2 x^{2}}+\frac{3}{2 \sqrt{2}} \arcsin \frac{4 x+3}{\sqrt{17}}\right)^{\prime}= \\ & =\frac{1}{2 \sqrt{1-3 x-2 x^{2}}} \cdot(-3-4 x)+\frac{3}{2 \sqrt{2}} \cdot \frac{1}{\sqrt{1-\left(\frac{4 x+3}{\sqrt{17}}\right)^{2}}} \cdot \frac{4}{\sqrt{17}}= \\ & =\frac...
-\frac{2x}{\sqrt{1-3x-2x^{2}}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,092
## Task Condition Find the derivative. $$ y=-\frac{1}{3 \sin ^{3} x}-\frac{1}{\sin x}+\frac{1}{2} \ln \frac{1+\sin x}{1-\sin x} $$
## Solution $y^{\prime}=\left(-\frac{1}{3 \sin ^{3} x}-\frac{1}{\sin x}+\frac{1}{2} \ln \frac{1+\sin x}{1-\sin x}\right)^{\prime}=$ $=-\frac{-3}{3 \sin ^{4} x} \cdot \cos x-\frac{-1}{\sin ^{2} x} \cdot \cos x+$ $+\frac{1}{2} \cdot \frac{1-\sin x}{1+\sin x} \cdot \frac{\cos x \cdot(1-\sin x)-(1+\sin x) \cdot(-\cos x)...
\frac{1}{\cosx\cdot\sin^{4}x}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,093
## Problem Statement Find the derivative $y_{x}^{\prime}$. $$ \left\{\begin{array}{l} x=\ln \sqrt{\frac{1-t}{1+t}} \\ y=\sqrt{1-t^{2}} \end{array}\right. $$
## Solution $$ \begin{aligned} & x_{t}^{\prime}=\left(\ln \sqrt{\frac{1-t}{1+t}}\right)^{\prime}=\sqrt{\frac{1+t}{1-t}} \cdot \frac{1}{2 \sqrt{\frac{1-t}{1+t}}} \cdot \frac{-1 \cdot(1+t)-(1-t) \cdot 1}{(1+t)^{2}}= \\ & =\sqrt{\frac{1+t}{1-t}} \cdot \frac{1}{2} \cdot \sqrt{\frac{1+t}{1-t}} \cdot \frac{-2}{(1+t)^{2}}=-\...
\cdot\sqrt{1-^{2}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,094
## Problem Statement Derive the equations of the tangent and normal lines to the curve at the point corresponding to the parameter value $t=t_{0}$. \[ \left\{\begin{array}{l} x=\frac{1}{2} \cdot t^{2}-\frac{1}{4} \cdot t^{4} \\ y=\frac{1}{2} \cdot t^{2}+\frac{1}{3} \cdot t^{3} \end{array}\right. \] $t_{0}=0$
## Solution Since $t_{0}=0$, then $$ \begin{aligned} & x_{0}=\frac{1}{2} \cdot 0^{2}-\frac{1}{4} \cdot 0^{4}=0 \\ & y_{0}=\frac{1}{2} \cdot 0^{2}+\frac{1}{3} \cdot 0^{3}=0 \end{aligned} $$ Find the derivatives: $x_{t}^{\prime}=\left(\frac{1}{2} \cdot t^{2}-\frac{1}{4} \cdot t^{4}\right)^{\prime}=t-t^{3}$ $y_{t}^{\p...
x-x
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,095
Condition of the problem Find the $n$-th order derivative. $y=\frac{2 x+5}{13(3 x+1)}$
## Solution $y=\frac{2 x+5}{13(3 x+1)}$ $y^{\prime}=\left(\frac{2 x+5}{13(3 x+1)}\right)^{\prime}=\frac{2 \cdot(3 x+1)-(2 x+5) \cdot 3}{13(3 x+1)^{2}}=$ $=\frac{6 x+2-6 x-15}{13(3 x+1)^{2}}=-\frac{13}{13(3 x+1)^{2}}=-\frac{1}{(3 x+1)^{2}}$ $y^{\prime \prime}=\left(y^{\prime}\right)^{\prime}=\left(-\frac{1}{(3 x+1)^...
y^{(n)}=\frac{(-1)^{n}\cdotn!\cdot3^{n-1}}{(3x+1)^{n+1}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,096
Condition of the problem Find the derivative of the specified order. $y=\left(1+x^{2}\right) \operatorname{arctg} x, y^{\prime \prime \prime}=?$
## Solution $y^{\prime}=\left(\left(1+x^{2}\right) \operatorname{arctg} x\right)^{\prime}=2 x \cdot \operatorname{arctg} x+\left(1+x^{2}\right) \cdot \frac{1}{1+x^{2}}=$ $=2 x \cdot \operatorname{arctg} x+1$ $y^{\prime \prime}=\left(y^{\prime}\right)^{\prime}=(2 x \cdot \operatorname{arctg} x+1)^{\prime}=2 \operator...
\frac{4}{(1+x^{2})^{2}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,097
## Problem Statement Find the second-order derivative $y_{x x}^{\prime \prime}$ of the function given parametrically. $$ \left\{\begin{array}{l} x=\sqrt{t-1} \\ y=\frac{t}{\sqrt{1-t}} \end{array}\right. $$
## Solution $x_{t}^{\prime}=(\sqrt{t-1})^{\prime}=\frac{1}{2 \sqrt{t-1}}$ $$ \begin{aligned} & y_{t}^{\prime}=\left(\frac{t}{\sqrt{1-t}}\right)^{\prime}=\frac{1 \cdot \sqrt{1-t}-t \cdot \frac{1}{2 \sqrt{1-t}} \cdot(-1)}{1-t}= \\ & =\frac{2(1-t)+t}{2 \sqrt{(1-t)^{3}}}=\frac{2-2 t+t}{2 \sqrt{(1-t)^{3}}}=\frac{2-t}{2 \s...
\frac{2}{\sqrt{(1-)^{3}}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
46,098
## Problem Statement Show that the function $y_{\text {satisfies equation (1). }}$. \[ \begin{aligned} & y=x(c-\ln x) \\ & (x-y) d x+x \cdot d y=0 \end{aligned} \]
## Solution $y^{\prime}=(x(c-\ln x))^{\prime}=(c-\ln x)+x\left(-\frac{1}{x}\right)=c-\ln x-1$ Equation (1): $(x-y) d x+x \cdot d y=0$ $x \cdot d y=(y-x) d x$ $x \cdot \frac{d y}{d x}=y-x$ $x \cdot y^{\prime}=y-x$ Substitute $y_{\text {and }} y^{\prime}$ : $x \cdot(c-\ln x-1)=x(c-\ln x)-x$ Simplify: $x \cdot(c-...
proof
Calculus
proof
Yes
Yes
olympiads
false
46,099
## Condition of the problem Prove that $\lim _{n \rightarrow \infty} a_{n}=a_{\text {(specify }} N(\varepsilon)$ ). $a_{n}=\frac{1-2 n^{2}}{2+4 n^{2}}, a=-\frac{1}{2}$
## Solution By the definition of the limit: $$ \begin{aligned} & \forall \varepsilon>0: \exists N(\varepsilon) \in \mathbb{N}: \forall n: n \geq N(\varepsilon):\left|a_{n}-a\right| \\ & \left|\frac{2-4 n^{2}+2+4 n^{2}}{2\left(2+4 n^{2}\right)}\right| \\ & \left|\frac{4}{2\left(2+4 n^{2}\right)}\right| \\ & \left|\fra...
proof
Calculus
proof
Yes
Yes
olympiads
false
46,100