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## Task Condition Find the derivative. $$ y=\frac{2}{3}\left(4 x^{2}-4 x+3\right) \sqrt{x^{2}-x}+(2 x-1)^{4} \cdot \arcsin \frac{1}{2 x-1}, 2 x-1>0 $$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\frac{2}{3}\left(4 x^{2}-4 x+3\right) \sqrt{x^{2}-x}+(2 x-1)^{4} \cdot \arcsin \frac{1}{2 x-1}\right)^{\prime}= \\ & =\frac{2}{3}\left((8 x-4) \sqrt{x^{2}-x}+\left(4 x^{2}-4 x+3\right) \cdot \frac{1}{2 \sqrt{x^{2}-x}} \cdot(2 x-1)\right)+ \\ & +\left(4(2 x-1) \cdot 2 \...
8(2x-1)\cdot\arcsin\frac{1}{2x-1}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,046
## Task Condition Find the derivative. $y=\operatorname{arctg} \sqrt{x^{2}-1}-\frac{\ln x}{\sqrt{x^{2}-1}}$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\operatorname{arctg} \sqrt{x^{2}-1}-\frac{\ln x}{\sqrt{x^{2}-1}}\right)^{\prime}= \\ & =\frac{1}{1+\left(\sqrt{x^{2}-1}\right)^{2}} \cdot \frac{1}{2 \sqrt{x^{2}-1}} \cdot 2 x-\frac{\frac{1}{x} \cdot \sqrt{x^{2}-1}-\ln x \cdot \frac{1}{2 \sqrt{x^{2}-1}} \cdot 2 x}{x^{2}...
\frac{x\cdot\lnx}{\sqrt{(x^{2}-1)^{3}}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,047
## Task Condition Find the derivative. $$ y=\frac{4^{x}(\ln 4 \cdot \sin 4 x-4 \cos 4 x)}{16+\ln ^{2} 4} $$
## Solution $y^{\prime}=\left(\frac{4^{x}(\ln 4 \cdot \sin 4 x-4 \cos 4 x)}{16+\ln ^{2} 4}\right)^{\prime}=$ $=\frac{1}{16+\ln ^{2} 4} \cdot\left(4^{x} \cdot \ln 4 \cdot(\ln 4 \cdot \sin 4 x-4 \cos 4 x)+4^{x}(4 \ln 4 \cdot \cos 4 x+16 \sin 4 x)\right)=$ $$ \begin{aligned} & =\frac{4^{x}}{16+\ln ^{2} 4} \cdot\left(\l...
4^{x}\cdot\sin4x
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,048
## Task Condition Find the derivative $y_{x}^{\prime}$. $$ \left\{\begin{array}{l} x=t \sqrt{t^{2}+1} \\ y=\ln \frac{1+\sqrt{1+t^{2}}}{t} \end{array}\right. $$
## Solution $x_{t}^{\prime}=\left(t \sqrt{t^{2}+1}\right)^{\prime}=\sqrt{t^{2}+1}+t \cdot \frac{1}{2 \sqrt{t^{2}+1}} \cdot 2 t=\sqrt{t^{2}+1}+\frac{t^{2}}{\sqrt{t^{2}+1}}=$ $=\frac{t^{2}+1+t^{2}}{\sqrt{t^{2}+1}}=\frac{2 t^{2}+1}{\sqrt{t^{2}+1}}$ $y_{t}^{\prime}=\left(\ln \frac{1+\sqrt{1-t^{2}}}{t}\right)^{\prime}=\f...
-\frac{1}{(2^{2}+1)}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,049
## Problem Statement Derive the equations of the tangent and normal lines to the curve at the point corresponding to the parameter value $t=t_{0}$. \[ \left\{ \begin{array}{l} x=t(1-\sin t) \\ y=t \cdot \cos t \end{array} \right. \] $t_{0}=0$
## Solution Since $t_{0}=0$, then $x_{0}=0 \cdot(1-\sin 0)=0$ $y_{0}=0 \cdot \cos 0=0$ Let's find the derivatives: $x_{t}^{\prime}=(t(1-\sin t))^{\prime}=(1-\sin t)-t \cdot \cos t$ $y_{t}^{\prime}=(t \cdot \cos t)^{\prime}=t \cdot \cos t-\sin t$ $y_{x}^{\prime}=\frac{y_{t}^{\prime}}{x_{t}^{\prime}}=\frac{t \cdot...
0,\;0
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,050
## Problem Statement Find the $n$-th order derivative. $y=a^{2 x+3}$
## Solution $y=a^{2 x+3}=a^{2 x} \cdot a^{3}=\left(e^{\ln a}\right)^{2 x} \cdot a^{3}=e^{2 x \cdot \ln a} \cdot a^{3}$ $y^{\prime}=\left(e^{2 x \cdot \ln a} \cdot a^{3}\right)^{\prime}=e^{2 x \cdot \ln a} \cdot 2 \ln a \cdot a^{3}$ $y^{\prime \prime}=\left(y^{\prime}\right)^{\prime}=\left(e^{2 x \cdot \ln a} \cdot 2...
^{2x+3}\cdot2^{n}\cdot\ln^{n}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,051
## Task Condition Find the derivative of the specified order. $$ y=\frac{\ln (2 x+5)}{2 x+5}, y^{\prime \prime \prime}=? $$
## Solution $$ \begin{aligned} & y^{\prime}=\left(\frac{\ln (2 x+5)}{2 x+5}\right)^{\prime}=\frac{\frac{1}{2 x+5} \cdot 2 \cdot(2 x+5)-\ln (2 x+5) \cdot 2}{(2 x+5)^{2}}= \\ & =\frac{2-2 \ln (2 x+5)}{(2 x+5)^{2}}=2 \cdot \frac{1-\ln (2 x+5)}{(2 x+5)^{2}} \\ & y^{\prime \prime}=\left(y^{\prime}\right)^{\prime}=\left(2 \...
\frac{88-48\ln(2x+5)}{(2x+5)^{4}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,052
## Problem Statement Find the second-order derivative $y_{x x}^{\prime \prime}$ of the function given parametrically. $$ \left\{\begin{array}{l} x=\cos t \\ y=\ln (\sin t) \end{array}\right. $$
## Solution $x_{t}^{\prime}=(\cos t)^{\prime}=-\sin t$ $y_{t}^{\prime}=(\ln (\sin t))^{\prime}=\frac{1}{\sin t} \cdot \cos t=\frac{\cos t}{\sin t}$ We obtain: $y_{x}^{\prime}=\frac{y_{t}^{\prime}}{x_{t}^{\prime}}=\left(\frac{\cos t}{\sin t}\right) /(-\sin t)=-\frac{\cos t}{\sin ^{2} t}$ $\left(y_{x}^{\prime}\right...
-\frac{1+\cos^{2}}{\sin^{4}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,053
## Problem Statement Show that the function $y$ satisfies equation (1). $$ \begin{aligned} & y=\sqrt[4]{\sqrt{x}+\sqrt{x+1}} \\ & 8 \cdot x \cdot y^{\prime}-y=\frac{-1}{y^{3} \sqrt{x+1}} \end{aligned} $$
## Solution $$ \begin{aligned} & y^{\prime}=(\sqrt[4]{\sqrt{x}+\sqrt{x+1}})^{\prime}=\frac{1}{4} \cdot \frac{1}{\sqrt[4]{(\sqrt{x}+\sqrt{x+1})^{3}}} \cdot\left(\frac{1}{2 \sqrt{x}}+\frac{1}{2 \sqrt{x+1}}\right)= \\ & =\frac{1}{4} \cdot \frac{1}{\sqrt[4]{(\sqrt{x}+\sqrt{x+1})^{3}}} \cdot \frac{\sqrt{x}+\sqrt{x+1}}{2 \s...
proof
Calculus
proof
Yes
Yes
olympiads
false
47,054
## Condition of the problem Prove that $\lim _{n \rightarrow \infty} a_{n}=a_{\text {(specify }} N(\varepsilon)$ ). $a_{n}=\frac{23-4 n}{2-n}, a=4$
## Solution By the definition of the limit: $\forall \varepsilon>0: \exists N(\varepsilon) \in \mathbb{N}: \forall n: n \geq N(\varepsilon):\left|a_{n}-a\right| \\ & \left|\frac{23-4 n-8+4 n}{2-n}\right| \\ & \left|\frac{15}{2-n}\right| \\ & \left|\frac{\frac{15}{n-2}}{n}\right| \\ & \frac{15}{n-2} \\ & n-2>\frac{15}...
N(\varepsilon)=3+[\frac{15}{\varepsilon}]
Calculus
proof
Yes
Yes
olympiads
false
47,055
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty} \frac{(n+1)^{3}-(n-1)^{3}}{(n+1)^{2}+(n-1)^{2}}$
## Solution $\lim _{n \rightarrow \infty} \frac{(n+1)^{3}-(n-1)^{3}}{(n+1)^{2}+(n-1)^{2}}=\lim _{n \rightarrow \infty} \frac{n^{3}+3 n^{2}+3 n+1-n^{3}+3 n^{2}-3 n+1}{n^{2}+2 n+1+n^{2}-2 n+1}=$ $=\lim _{n \rightarrow \infty} \frac{6 n^{2}+2}{2 n^{2}+2}=\lim _{n \rightarrow \infty} \frac{\frac{1}{n^{2}}\left(3 n^{2}+1\...
3
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,056
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty} \frac{n \sqrt{71 n}-\sqrt[3]{64 n^{6}+9}}{(n-\sqrt[3]{n}) \sqrt{11+n^{2}}}$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{n \sqrt{71 n}-\sqrt[3]{64 n^{6}+9}}{(n-\sqrt[3]{n}) \sqrt{11+n^{2}}}=\lim _{n \rightarrow \infty} \frac{\frac{1}{n^{2}}\left(n \sqrt{71 n}-\sqrt[3]{64 n^{6}+9}\right)}{\frac{1}{n^{2}}(n-\sqrt[3]{n}) \sqrt{11+n^{2}}}= \\ & =\lim _{n \rightarrow \infty}...
-4
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,057
## Problem Statement Calculate the limit of the numerical sequence: $$ \lim _{n \rightarrow \infty}(n \sqrt{n}-\sqrt{n(n+1)(n+2)}) $$
## Solution $\lim _{n \rightarrow \infty}(n \sqrt{n}-\sqrt{n(n+1)(n+2)})=$ $$ \begin{aligned} & =\lim _{n \rightarrow \infty} \frac{(n \sqrt{n}-\sqrt{n(n+1)(n+2)})(n \sqrt{n}+\sqrt{n(n+1)(n+2)})}{n \sqrt{n}+\sqrt{n(n+1)(n+2)}}= \\ & =\lim _{n \rightarrow \infty} \frac{n^{3}-n(n+1)(n+2)}{n \sqrt{n}+\sqrt{n(n+1)(n+2)}}...
-\infty
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,058
## Problem Statement Calculate the limit of the numerical sequence: $$ \lim _{n \rightarrow \infty} \frac{1-2+3-4+\ldots+(2 n-1)-2 n}{\sqrt[3]{n^{3}+2 n+2}} $$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{1-2+3-4+\ldots+(2 n-1)-2 n}{\sqrt[3]{n^{3}+2 n+2}}= \\ & =\{1-2=3-4=\ldots=(2 n-1)-2 n=-1\}= \\ & =\lim _{n \rightarrow \infty} \frac{-1 \cdot n}{\sqrt[3]{n^{3}+2 n+2}}=\lim _{n \rightarrow \infty} \frac{\frac{1}{n} \cdot(-1) \cdot n}{\frac{1}{n} \sqr...
-1
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,059
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty}\left(\frac{2 n-1}{2 n+1}\right)^{n+1}$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty}\left(\frac{2 n-1}{2 n+1}\right)^{n+1}=\lim _{n \rightarrow \infty}\left(\frac{2 n+1}{2 n-1}\right)^{-n-1}= \\ & =\lim _{n \rightarrow \infty}\left(\frac{2 n-1+2}{2 n-1}\right)^{-n-1}=\lim _{n \rightarrow \infty}\left(1+\frac{2}{2 n-1}\right)^{-n-1}= \\ & =\...
\frac{1}{e}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,060
## Task Condition Prove that (find $\delta(\varepsilon)$ : $$ \lim _{x \rightarrow 10} \frac{5 x^{2}-51 x+10}{x-10}=49 $$
## 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_fcfb644d65eb046b31c7g-04.jpg?height=82&width=1491&top_left...
\delta(\varepsilon)=\frac{\varepsilon}{5}
Calculus
proof
Yes
Yes
olympiads
false
47,061
## problem statement Prove that the function $f(x)_{\text {is continuous at the point }} x_{0 \text { (find }} \delta(\varepsilon)_{\text {): }}$ : $f(x)=-3 x^{2}-9, x_{0}=3$
## Solution By definition, the function $f(x)_{\text {is continuous at the point }} x=x_{0}$, if $\forall \varepsilon>0: \exists \delta(\varepsilon)>0$ : $$ \left|x-x_{0}\right|0_{\text {there exists such }} \delta(\varepsilon)>0$, such that $\left|f(x)-f\left(x_{0}\right)\right|<\varepsilon_{\text {when }}$ $\left|x...
proof
Calculus
proof
Yes
Yes
olympiads
false
47,062
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow-3} \frac{x^{2}+2 x-3}{x^{3}+4 x^{2}+3 x}$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow-3} \frac{x^{2}+2 x-3}{x^{3}+4 x^{2}+3 x}=\left\{\frac{0}{0}\right\}=\lim _{x \rightarrow-3} \frac{(x+3)(x-1)}{(x+3)\left(x^{2}+x\right)}= \\ & =\lim _{x \rightarrow-3} \frac{x-1}{x^{2}+x}=\frac{-3-1}{(-3)^{2}-3}=\frac{-4}{9-3}=-\frac{4}{6}=-\frac{2}{3} \end{aligned...
-\frac{2}{3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,063
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 8} \frac{\sqrt{9+2 x}-5}{\sqrt[3]{x}-2}$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow 8} \frac{\sqrt{9+2 x}-5}{\sqrt[3]{x}-2}=\lim _{x \rightarrow 8} \frac{(\sqrt{9+2 x}-5)(\sqrt{9+2 x}+5)}{(\sqrt[3]{x}-2)(\sqrt{9+2 x}+5)}= \\ & =\lim _{x \rightarrow 8} \frac{9+2 x-25}{(\sqrt[3]{x}-2)(\sqrt{9+2 x}+5)}=\lim _{x \rightarrow 8} \frac{2 x-16}{(\sqrt[3]{...
\frac{12}{5}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,064
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0} \frac{\arcsin 2 x}{\ln (e-x)-1}$
## Solution We will use the substitution of equivalent infinitesimals: $\arcsin 2 x \sim 2 x$, as $x \rightarrow 0 (2 x \rightarrow 0)$ $\ln \left(1+\left(-\frac{x}{e}\right)\right) \sim -\frac{x}{e}$, as $x \rightarrow 0 \left(-\frac{x}{e} \rightarrow 0\right)$ We obtain: $$ \begin{aligned} & \lim _{x \rightarrow...
-2e
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,065
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 2} \frac{\operatorname{arctg}\left(x^{2}-2 x\right)}{\sin 3 \pi x}$
## Solution Substitution: $x=y+2 \Rightarrow y=x-2$ $x \rightarrow 2 \Rightarrow y \rightarrow 0$ We get: $\lim _{x \rightarrow 2} \frac{\operatorname{arctg}\left(x^{2}-2 x\right)}{\sin 3 \pi x}=\lim _{y \rightarrow 0} \frac{\operatorname{arctg}\left((y+2)^{2}-2(y+2)\right)}{\sin 3 \pi(y+2)}=$ $=\lim _{y \rightar...
\frac{2}{3\pi}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,066
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow \frac{\pi}{2}} \frac{\ln (\sin x)}{(2 x-\pi)^{2}}$
## Solution Substitution: $x=y+\frac{\pi}{2} \Rightarrow y=x-\frac{\pi}{2}$ $x \rightarrow \frac{\pi}{2} \Rightarrow y \rightarrow 0$ We get: $$ \begin{aligned} & \lim _{x \rightarrow \frac{\pi}{2}} \frac{\ln (\sin x)}{(2 x-\pi)^{2}}=\lim _{y \rightarrow 0} \frac{\ln \left(\sin \left(y+\frac{\pi}{2}\right)\right)}...
-\frac{1}{8}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,067
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0} \frac{e^{x}-e^{-2 x}}{x+\sin x^{2}}$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow 0} \frac{e^{x}-e^{-2 x}}{x+\sin x^{2}}=\lim _{x \rightarrow 0} \frac{\left(e^{x}-1\right)-\left(e^{-2 x}-1\right)}{x+\sin x^{2}}= \\ & =\lim _{x \rightarrow 0} \frac{\frac{1}{x}\left(\left(e^{x}-1\right)-\left(e^{-2 x}-1\right)\right)}{\frac{1}{x}\left(x+\sin x^{2}...
3
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,068
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 0} \frac{3^{x+1}-3}{\ln \left(1+x \sqrt{1+x e^{x}}\right)} $$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow 0} \frac{3^{x+1}-3}{\ln \left(1+x \sqrt{1+x e^{x}}\right)}=\lim _{x \rightarrow 0} \frac{3\left(3^{x}-1\right)}{\ln \left(1+x \sqrt{1+x e^{x}}\right)}= \\ & =\lim _{x \rightarrow 0} \frac{3\left(\left(e^{\ln 3}\right)^{x}-1\right)}{\ln \left(1+x \sqrt{1+x e^{x}}\ri...
3\ln3
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,069
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 0}\left(\frac{1+\tan x \cdot \cos 2 x}{1+\tan x \cdot \cos 5 x}\right)^{\frac{1}{x^{3}}} $$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow 0}\left(\frac{1+\tan x \cdot \cos 2 x}{1+\tan x \cdot \cos 5 x}\right)^{\frac{1}{x^{3}}}= \\ & =\lim _{x \rightarrow 0}\left(e^{\ln \left(\frac{1+\tan x \cdot \cos 2 x}{1+\tan x \cdot \cos 5 x}\right)}\right)^{\frac{1}{x^{3}}}= \\ & =\lim _{x \rightarrow 0} e^{\fra...
e^{\frac{21}{2}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,070
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0}\left(\frac{\sin 5 x^{2}}{\sin x}\right)^{\frac{1}{x+6}}$
## Solution $\lim _{x \rightarrow 0}\left(\frac{\sin 5 x^{2}}{\sin x}\right)^{\frac{1}{x+6}}=\left(\lim _{x \rightarrow 0} \frac{\sin 5 x^{2}}{\sin x}\right)^{\lim _{x \rightarrow 0} \frac{1}{x+6}}=$ $=\left(\lim _{x \rightarrow 0} \frac{\sin 5 x^{2}}{\sin x}\right)^{\frac{1}{0+6}}=\left(\lim _{x \rightarrow 0} \frac...
0
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,071
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 3}\left(\frac{\sin x}{\sin 3}\right)^{\frac{1}{x-3}}$
## Solution $\lim _{x \rightarrow 3}\left(\frac{\sin x}{\sin 3}\right)^{\frac{1}{x-3}}=\lim _{x \rightarrow 3}\left(e^{\ln \left(\frac{\sin x}{\sin 3}\right)}\right)^{\frac{1}{x-3}}=$ $=\lim _{x \rightarrow 3} e^{\frac{1}{x-3} \cdot \ln \left(\frac{\sin x}{\sin 3}\right)}=\exp \left\{\lim _{x \rightarrow 3} \frac{1}{...
e^{\cot3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,072
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow \frac{1}{2}}(\arcsin x+\arccos x)^{\frac{1}{x}}$
## Solution $\lim _{x \rightarrow \frac{1}{2}}(\arcsin x+\arccos x)^{\frac{1}{x}}=\left(\arcsin \frac{1}{2}+\arccos \frac{1}{2}\right)^{\frac{1}{\left(\frac{1}{2}\right)}}=\left(\frac{\pi}{6}+\frac{\pi}{3}\right)^{2}=\left(\frac{\pi}{2}\right)^{2}=\frac{\pi^{2}}{4}$ ## Problem Kuznetsov Limits 20-26
\frac{\pi^{2}}{4}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,073
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 2} \sqrt[3]{\lg (x+2)+\sin \sqrt{4-x^{2}} \cdot \cos \frac{x+2}{x-2}} $$
## Solution Since $\cos \frac{x+2}{x-2}$ is bounded, and $\sin \sqrt{4-x^{2}} \rightarrow 0$, as $x \rightarrow 2$, then $\sin \sqrt{4-x^{2}} \cdot \cos \frac{x+2}{x-2} \rightarrow 0$, as $x \rightarrow 2$ Then: $\lim _{x \rightarrow 2} \sqrt[3]{\lg (x+2)+\sin \sqrt{4-x^{2}} \cdot \cos \frac{x+2}{x-2}}=\sqrt[3]{\lg ...
\sqrt[3]{\lg4}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,074
## Problem Statement Write the decomposition of vector $x$ in terms of vectors $p, q, r$: $x=\{11 ; 5 ;-3\}$ $p=\{1 ; 0 ; 2\}$ $q=\{-1 ; 0 ; 1\}$ $r=\{2 ; 5 ;-3\}$
## 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-6q+r
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,075
## Problem Statement Are the vectors $c_{1 \text { and }} c_{2}$, constructed from vectors $a \text{ and } b$, collinear? $a=\{-1 ; 2 ;-1\}$ $b=\{2 ;-7 ; 1\}$ $c_{1}=6 a-2 b$ $c_{2}=b-3 a$
## 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 $c_{1}=-2(b-3 a)=-2 c_{2}$ for any $a$ and $b$. That is, $c_{1}=-2 \cdot c_{2}$, which means the vectors $c_{1}...
c_{1}=-2\cdotc_{2}
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,076
## Problem Statement Find the cosine of the angle between vectors $\overrightarrow{A B}$ and $\overrightarrow{A C}$. $A(2, -8, -1), B(4, -6, 0), C(-2, -5, -1)$
## Solution Let's find $\overrightarrow{A B}$ and $\overrightarrow{A C}$: $\overrightarrow{A B}=(4-2 ;-6-(-8) ; 0-(-1))=(2 ; 2 ; 1)$ $\overrightarrow{A C}=(-2-2 ;-5-(-8) ;-1-(-1))=(-4 ; 3 ; 0)$ We find the cosine of the angle $\phi_{\text {between vectors }} \overrightarrow{A B}$ and $\overrightarrow{A C}$: $\cos ...
-\frac{2}{15}
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,077
## Problem Statement Calculate the area of the parallelogram constructed on vectors $a$ and $b$. \[ \begin{aligned} & a=2 p+3 q \\ & b=p-2 q \\ & |p|=2 \\ & |q|=3 \\ & (\widehat{p, q})=\frac{\pi}{4} \end{aligned} \]
## 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: $$ \begin{aligned} & a \times b=(2 p+3 q) \times(p-2 q)=2 \cdot p \times p+2 \cdot(-2) \c...
21\sqrt{2}
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,078
## Task Condition Are the vectors $a, b$ and $c$ coplanar? $a=\{5 ; 3 ; 4\}$ $b=\{-1 ; 0 ;-1\}$ $c=\{4 ; 2 ; 4\}$
## Solution For three vectors to be coplanar (lie in the same plane or parallel planes), it is necessary and sufficient that their scalar triple product $(a, b, c)$ be equal to zero. $$ \begin{aligned} & (a, b, c)=\left|\begin{array}{ccc} 5 & 3 & 4 \\ -1 & 0 & -1 \\ 4 & 2 & 4 \end{array}\right|= \\ & =5 \cdot\left|\b...
2\neq0
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,079
## Problem Statement Calculate the volume of the tetrahedron with vertices at points \( A_{1}, A_{2}, A_{3}, A_{4} \) and its height dropped from vertex \( A_{4} \) to the face \( A_{1} A_{2} A_{3} \). \( A_{1}(1 ; 1 ;-1) \) \( A_{2}(2 ; 3 ; 1) \) \( A_{3}(3 ; 2 ; 1) \) \( A_{4}(5 ; 9 ;-8) \)
## Solution From vertex $A_{1}$, we draw vectors: $\overrightarrow{A_{1} A_{2}}=\{2-1 ; 3-1 ; 1-(-1)\}=\{1 ; 2 ; 2\}$ $\overrightarrow{A_{1} A_{3}}=\{3-1 ; 2-1 ; 1-(-1)\}=\{2 ; 1 ; 2\}$ $\vec{A}_{1} A_{4}=\{5-1 ; 9-1 ;-8-(-1)\}=\{4 ; 8 ;-7\}$ According to the geometric meaning of the scalar triple product, we have...
7.5
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,080
## Problem Statement Find the distance from the point $M_{0}$ to the plane passing through three points $M_{1}, M_{2}, M_{3}$. $M_{1}(1 ; -1 ; 2)$ $M_{2}(2 ; 1 ; 2)$ $M_{3}(1 ; 1 ; 4)$ $M_{0}(-3 ; 2 ; 7)$
## Solution Find the equation of the plane passing through three points $M_{1}, M_{2}, M_{3}$: $$ \left|\begin{array}{lll} x-1 & y-(-1) & z-2 \\ 2-1 & 1-(-1) & 2-2 \\ 1-1 & 1-(-1) & 4-2 \end{array}\right|=0 $$ Perform transformations: $$ \left|\begin{array}{ccc} x-1 & y+1 & z-2 \\ 1 & 2 & 0 \\ 0 & 2 & 2 \end{array}...
\sqrt{6}
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,081
## Problem Statement Write the equation of the plane passing through point $A$ and perpendicular to vector $\overrightarrow{B C}$. $A(1; -1; 5)$ $B(0; 7; 8)$ $C(-1; 3; 8)$
## Solution Let's find the vector $\overrightarrow{BC}$: $\overrightarrow{BC}=\{-1-0 ; 3-7 ; 8-8\}=\{-1 ;-4 ; 0\}$ Since the vector $\overrightarrow{BC}$ is perpendicular to the desired plane, it can be taken as the normal vector. Therefore, the equation of the plane will be: $-(x-1)-4 \cdot(y-(-1))+0 \cdot(z-5)=0$...
x+4y+3=0
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,082
## Task Condition Find the angle between the planes: $x+2 y+2 z-3=0$ $2 x-y+2 z+5=0$
## Solution The dihedral angle between planes is equal to the angle between their normal vectors. The normal vectors of the given planes are: $\overrightarrow{n_{1}}=\{1 ; 2 ; 2\}$ $\overrightarrow{n_{2}}=\{2 ;-1 ; 2\}$ The angle $\phi$ between the planes is determined by the formula: $$ \begin{aligned} & \cos \ph...
\arccos\frac{4}{9}\approx63^{0}36^{\}44^{\\}
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,083
## Problem Statement Find the coordinates of point $A$, which is equidistant from points $B$ and $C$. $A(0 ; y ; 0)$ $B(-2 ;-4 ; 6)$ $C(7 ; 2 ; 5)$
## Solution Let's find the distances $A B$ and $A C$: $$ \begin{aligned} & A B=\sqrt{(-2-0)^{2}+(-4-y)^{2}+(6-0)^{2}}=\sqrt{4+16+8 y+y^{2}+36}=\sqrt{y^{2}+8 y+56} \\ & A C=\sqrt{(7-0)^{2}+(2-y)^{2}+(5-0)^{2}}=\sqrt{49+4-4 y+y^{2}+25}=\sqrt{y^{2}-4 y+78} \end{aligned} $$ Since by the condition of the problem $A B=A C...
A(0;1\frac{5}{6};0)
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,084
## 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 $a$? $A(-2; -1; 1)$ $a: x-2y+6z-10=0$ $k=\frac{3}{5}$
## 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 $a$: $a^{\prime}: x-2 y+6 z-6=0$ Substitute the coordinates of point $A$ into the equat...
0
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,085
## Task Condition Write the canonical equations of the line. $6 x-5 y-4 z+8=0$ $6 x+5 y+3 z+4=0$
## Solution Canonical equations of a line: $\frac{x-x_{0}}{m}=\frac{y-y_{0}}{n}=\frac{z-z_{0}}{p}$ where $\left(x_{0} ; y_{0} ; z_{0}\right)_{\text {- are coordinates of some point on the line, and }} \vec{s}=\{m ; n ; p\}$ - its direction vector. Since the line belongs to both planes simultaneously, its direction v...
\frac{x+1}{5}=\frac{y-\frac{2}{5}}{-42}=\frac{z}{60}
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,086
## Problem Statement Find the point of intersection of the line and the plane. $\frac{x-2}{2}=\frac{y-2}{-1}=\frac{z-4}{3}$ $x+3 y+5 z-42=0$
## Solution Let's write the parametric equations of the line. $$ \begin{aligned} & \frac{x-2}{2}=\frac{y-2}{-1}=\frac{z-4}{3}=t \Rightarrow \\ & \left\{\begin{array}{l} x=2+2 t \\ y=2-t \\ z=4+3 t \end{array}\right. \end{aligned} $$ Substitute into the equation of the plane: $(2+2 t)+3(2-t)+5(4+3 t)-42=0$ $2+2 t+6...
(4;1;7)
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,087
## Task Condition Find the point $M^{\prime}$ symmetric to the point $M$ with respect to the line. $M(0; -3; -2)$ $$ \frac{x-0.5}{0}=\frac{y+1.5}{-1}=\frac{z-1.5}{1} $$
## Solution We find the equation of the plane that is perpendicular to the given line and passes through the point $M$. Since the plane is perpendicular to the given line, we can use the direction vector of the line as its normal vector: $\vec{n}=\vec{s}=\{0 ;-1 ; 1\}$ Then the equation of the desired plane is: $0 ...
M^{\}(1;2;3)
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,088
## Condition of the problem Prove that $\lim _{n \rightarrow \infty} a_{n}=a_{\text {(specify }} N(\varepsilon)$ ). $a_{n}=\frac{4 n^{2}+1}{3 n^{2}+2}, a=\frac{4}{3}$
## Solution By the definition of the limit: $\forall \varepsilon>0: \exists N(\varepsilon) \in \mathbb{N}: \forall n: n \geq N(\varepsilon):\left|a_{n}-a\right| \\ & \left|\frac{12 n^{2}+3-12 n^{2}-8}{3\left(3 n^{2}+2\right)}\right| \\ & \left.\frac{-5}{3\left(3 n^{2}+2\right)} \right\rvert\, \\ & \frac{5}{3\left(3 n...
proof
Calculus
proof
Yes
Yes
olympiads
false
47,089
## Problem Statement Calculate the limit of the numerical sequence: $$ \lim _{n \rightarrow \infty} \frac{(n+1)^{3}-(n+1)^{2}}{(n-1)^{3}-(n+1)^{3}} $$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{(n+1)^{3}-(n+1)^{2}}{(n-1)^{3}-(n+1)^{3}}=\lim _{n \rightarrow \infty} \frac{(n+1)^{2} \cdot((n+1)-1)}{n^{3}-3 n^{2}+3 n-1-n^{3}-3 n^{2}-3 n-1}= \\ & =\lim _{n \rightarrow \infty} \frac{n(n+1)^{2}}{-6 n^{2}-2}=\lim _{n \rightarrow \infty} \frac{n^{3}\...
-\infty
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,090
## Problem Statement Calculate the limit of the numerical sequence: $$ \lim _{n \rightarrow \infty} \frac{n \sqrt[5]{n}-\sqrt[3]{27 n^{6}+n^{2}}}{(n+\sqrt[4]{n}) \sqrt{9+n^{2}}} $$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{n \sqrt[5]{n}-\sqrt[3]{27 n^{6}+n^{2}}}{(n+\sqrt[4]{n}) \sqrt{9+n^{2}}}=\lim _{n \rightarrow \infty} \frac{\frac{1}{n^{2}}\left(n \sqrt[5]{n}-\sqrt[3]{27 n^{6}+n^{2}}\right)}{\frac{1}{n^{2}}(n+\sqrt[4]{n}) \sqrt{9+n^{2}}}= \\ & =\lim _{n \rightarrow \...
-3
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,091
## Problem Statement Calculate the limit of the numerical sequence: $$ \lim _{n \rightarrow \infty}\left(\sqrt{n^{2}-3 n+2}-n\right) $$
## Solution $\lim _{n \rightarrow \infty}\left(\sqrt{n^{2}-3 n+2}-n\right)=\lim _{n \rightarrow \infty} \frac{\left(\sqrt{n^{2}-3 n+2}-n\right)\left(\sqrt{n^{2}-3 n+2}+n\right)}{\sqrt{n^{2}-3 n+2}+n}=$ $=\lim _{n \rightarrow \infty} \frac{n^{2}-3 n+2-n^{2}}{\sqrt{n^{2}-3 n+2}+n}=\lim _{n \rightarrow \infty} \frac{-3 n...
-\frac{3}{2}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,092
## Problem Statement Calculate the limit of the numerical sequence: $$ \lim _{n \rightarrow \infty} \frac{1+3+5+\ldots+(2 n-1)}{1+2+3+\ldots+n} $$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{1+3+5+\ldots+(2 n-1)}{1+2+3+\ldots+n}= \\ & =\lim _{n \rightarrow \infty} \frac{1}{1+2+3+\ldots+n} \cdot \frac{(1+(2 n-1)) n}{2}= \\ & =\lim _{n \rightarrow \infty} \frac{1}{1+2+3+\ldots+n} \cdot n^{2}=\lim _{n \rightarrow \infty} \frac{1}{\frac{(1+n)...
2
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,093
## Problem Statement Calculate the limit of the numerical sequence: $$ \lim _{n \rightarrow \infty}\left(\frac{3 n^{2}-6 n+7}{3 n^{2}+20 n-1}\right)^{-n+1} $$
## Solution $\lim _{n \rightarrow \infty}\left(\frac{3 n^{2}-6 n+7}{3 n^{2}+20 n-1}\right)^{-n+1}=\lim _{n \rightarrow \infty}\left(\frac{3 n^{2}+20 n-1}{3 n^{2}-6 n+7}\right)^{n-1}=$ $$ \begin{aligned} & =\lim _{n \rightarrow \infty}\left(\frac{3 n^{2}-6 n+7+26 n-8}{3 n^{2}-6 n+7}\right)^{n-1}= \\ & =\lim _{n \right...
e^{\frac{26}{3}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,094
## Condition of the problem Prove that (find $\delta(\varepsilon)$ : $\lim _{x \rightarrow \frac{1}{2}} \frac{6 x^{2}-x-1}{x-\frac{1}{2}}=5$
## 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 \( M \). A number \( A \in \mathbb{R} \) is called the limit of the function \( f \) as \( x \) approaches \( a (x \rightarrow...
\delta(\varepsilon)=\frac{\varepsilon}{6}
Calculus
proof
Yes
Yes
olympiads
false
47,095
## problem statement Prove that the function $f(x)_{\text {is continuous at the point }} x_{0 \text { (find }} \delta(\varepsilon)_{\text {) }}$ : $f(x)=-3 x^{2}-6, x_{0}=1$
## Solution By definition, the function $f(x)_{\text {is continuous at the point }} x=x_{0}$, if $\forall \varepsilon>0: \exists \delta(\varepsilon)>0$ : $$ \left|x-x_{0}\right|0_{\text {there exists such }} \delta(\varepsilon)>0$, such that $\left|f(x)-f\left(x_{0}\right)\right|<\varepsilon$ when $\left|x-x_{0}\righ...
proof
Calculus
proof
Yes
Yes
olympiads
false
47,096
Condition of the problem Calculate the limit of the function: $\lim _{x \rightarrow-1} \frac{\left(x^{3}-2 x-1\right)^{2}}{x^{4}+2 x+1}$
Solution $\lim _{x \rightarrow-1} \frac{\left(x^{3}-2 x-1\right)^{2}}{x^{4}+2 x+1}=\left\{\frac{0}{0}\right\}=\lim _{x \rightarrow-1} \frac{\left(x^{2}-x-1\right)^{2}(x+1)^{2}}{\left(x^{3}-x^{2}+x+1\right)(x+1)}=$ $=\lim _{x \rightarrow-1} \frac{\left(x^{2}-x-1\right)^{2}(x+1)}{x^{3}-x^{2}+x+1}=\frac{\left((-1)^{2}-(-...
0
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,097
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 16} \frac{\sqrt[4]{x}-2}{\sqrt{x}-4} $$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow 16} \frac{\sqrt[4]{x}-2}{\sqrt{x}-4}=\left\{\frac{0}{0}\right\}=\lim _{x \rightarrow 16} \frac{\sqrt[4]{x}-2}{(\sqrt[4]{x}-2)(\sqrt[4]{x}+2)}= \\ & =\lim _{x \rightarrow 16} \frac{1}{\sqrt[4]{x}+2}=\frac{1}{\sqrt[4]{16}+2}=\frac{1}{2+2}=\frac{1}{4} \end{aligned} $$
\frac{1}{4}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,098
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0} \frac{2 x}{\tan\left(2 \pi\left(x+\frac{1}{2}\right)\right)}$
## Solution We will use the substitution of equivalent infinitesimals: $\operatorname{tg} 2 \pi x \sim 2 \pi x$, as $x \rightarrow 0 (2 \pi x \rightarrow 0)$ We get: $$ \begin{aligned} & \lim _{x \rightarrow 0} \frac{2 x}{\operatorname{tg}\left(2 \pi\left(x+\frac{1}{2}\right)\right)}=\lim _{x \rightarrow 0} \frac{2...
\frac{1}{\pi}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,099
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow \frac{\pi}{2}} \frac{\tan 3x}{\tan x}$
## Solution Substitution: $x=y+\frac{\pi}{2} \Rightarrow y=x-\frac{\pi}{2}$ $x \rightarrow \frac{\pi}{2} \Rightarrow y \rightarrow 0$ We get: $$ \begin{aligned} & \lim _{x \rightarrow \frac{\pi}{2}} \frac{\tan 3 x}{\tan x}=\lim _{y \rightarrow 0} \frac{\tan 3\left(y+\frac{\pi}{2}\right)}{\tan \left(y+\frac{\pi}{2}...
\frac{1}{3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,100
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow \frac{\pi}{6}} \frac{\ln (\sin 3 x)}{(6 x-\pi)^{2}} $$
## Solution Substitution: $x=y+\frac{\pi}{6} \Rightarrow y=x-\frac{\pi}{6}$ $x \rightarrow \frac{\pi}{6} \Rightarrow y \rightarrow 0$ We get: $$ \begin{aligned} & \lim _{x \rightarrow \frac{\pi}{6}} \frac{\ln (\sin 3 x)}{(6 x-\pi)^{2}}=\lim _{y \rightarrow 0} \frac{\ln \left(\sin 3\left(y+\frac{\pi}{6}\right)\righ...
-\frac{1}{8}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,101
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0} \frac{e^{2 x}-e^{3 x}}{\operatorname{arctg} x-x^{2}}$
## Solution $\lim _{x \rightarrow 0} \frac{e^{2 x}-e^{3 x}}{\operatorname{arctg} x-x^{2}}=\lim _{x \rightarrow 0} \frac{\left(e^{2 x}-1\right)-\left(e^{3 x}-1\right)}{\operatorname{arctg} x-x^{2}}=$ $=\lim _{x \rightarrow 0} \frac{\frac{1}{x}\left(\left(e^{2 x}-1\right)-\left(e^{3 x}-1\right)\right)}{\frac{1}{x}\left...
-1
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,102
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0} \frac{e^{\alpha x}-e^{\beta x}}{\sin \alpha x-\sin \beta x}$
## Solution $\lim _{x \rightarrow 0} \frac{e^{\alpha x}-e^{\beta x}}{\sin \alpha x-\sin \beta x}=\lim _{x \rightarrow 0} \frac{\left(e^{\alpha x}-1\right)-\left(e^{\beta x}-1\right)}{2 \sin \frac{x(\alpha-\beta)}{2} \cos \frac{x(\alpha+\beta)}{2}}=$ $=\lim _{x \rightarrow 0} \frac{e^{\alpha x}-1}{2 \sin \frac{x(\alpha...
1
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,103
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0}\left(5-\frac{4}{\cos x}\right)^{\frac{1}{\sin ^{2} 3 x}}$
## Solution $\lim _{x \rightarrow 0}\left(5-\frac{4}{\cos x}\right)^{\frac{1}{\sin ^{2} 3 x}}=\lim _{x \rightarrow 0}\left(e^{\ln \left(5-\frac{4}{\cos x}\right)}\right)^{\frac{1}{\sin ^{2} 3 x}}=$ $=\lim _{x \rightarrow 0} e^{\frac{\ln \left(5-\frac{4}{\cos x}\right)}{\sin ^{2} 3 x}}=\exp \left\{\lim _{x \rightarrow ...
e^{-\frac{2}{9}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,104
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0}\left(\frac{x^{2}+4}{x+2}\right)^{x^{2}+3}$
## Solution $\lim _{x \rightarrow 0}\left(\frac{x^{2}+4}{x+2}\right)^{x^{2}+3}=\left(\frac{0^{2}+4}{0+2}\right)^{0^{2}+3}=$ $=\left(\frac{4}{2}\right)^{3}=2^{3}=8$ ## Problem Kuznetsov Limits 18-6
8
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,105
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow \frac{\pi}{4}}(\tan x)^{1 / \cos \left(\frac{3 \pi}{4}-x\right)}$
## Solution $\lim _{x \rightarrow \frac{\pi}{4}}(\operatorname{tg} x)^{1 / \cos \left(\frac{3 \pi}{4}-x\right)}=\lim _{x \rightarrow \frac{\pi}{4}}\left(e^{\ln (\operatorname{tg} x)}\right)^{1 / \cos \left(\frac{3 \pi}{4}-x\right)}=$ $=\lim _{x \rightarrow \frac{\pi}{4}} e^{\ln (\operatorname{tg} x) / \cos \left(\fra...
e^2
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,106
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow \frac{\pi}{6}}(\sin x)^{\frac{6 x}{\pi}}$
## Solution $\lim _{x \rightarrow \frac{\pi}{6}}(\sin x)^{\frac{6 x}{\pi}}=\left(\sin \frac{\pi}{6}\right)^{\frac{6}{\pi} \cdot \frac{\pi}{6}}=\left(\frac{1}{2}\right)^{1}=\frac{1}{2}$ ## Problem Kuznetsov Limits 20-6
\frac{1}{2}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,107
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty} \frac{\sqrt[4]{2+n^{5}}-\sqrt{2 n^{3}+3}}{(n+\sin n) \sqrt{7 n}}$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{\sqrt[4]{2+n^{5}}-\sqrt{2 n^{3}+3}}{(n+\sin n) \sqrt{7 n}}=\lim _{n \rightarrow \infty} \frac{\frac{1}{n \sqrt{n}}\left(\sqrt[4]{2+n^{5}}-\sqrt{2 n^{3}+3}\right)}{\frac{1}{n \sqrt{n}}(n+\sin n) \sqrt{7 n}}= \\ & =\lim _{n \rightarrow \infty} \frac{\sq...
-\frac{\sqrt{2}}{\sqrt{7}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,108
## Condition of the problem Prove that $\lim _{n \rightarrow \infty} a_{n}=a_{\text {(specify }} N(\varepsilon)$ ). $a_{n}=\frac{3 n-1}{5 n+1}, a=\frac{3}{5}$
## Solution By the definition of the limit: $\forall \varepsilon>0: \exists N(\varepsilon) \in \mathbb{N}: \forall n: n \geq N(\varepsilon):\left|a_{n}-a\right| \\ & \left.\frac{-8}{5(5 n+1)} \right\rvert\, \\ & \left|\frac{8}{5(5 n+1)}\right| \\ & \frac{8}{5(5 n+1)} \end{aligned} $$ $5 n+1>\frac{8}{5 \varepsilon} ;...
N(\varepsilon)=[\frac{8+20\varepsilon}{25\varepsilon}]
Calculus
proof
Yes
Yes
olympiads
false
47,109
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty} \frac{(2 n+1)^{3}-(2 n+3)^{3}}{(2 n+1)^{2}+(2 n+3)^{2}}$
## Solution $\lim _{n \rightarrow \infty} \frac{(2 n+1)^{3}-(2 n+3)^{3}}{(2 n+1)^{2}+(2 n+3)^{2}}=\lim _{n \rightarrow \infty} \frac{8 n^{3}+3 \cdot 4 n^{2}+3 \cdot 2 n+1-8 n^{3}-3 \cdot 3 \cdot 4 n^{2}-3 \cdot 3^{2} \cdot 2 n-3^{3}}{(2 n+1)^{2}+(2 n+3)^{2}}=$ $=\lim _{n \rightarrow \infty} \frac{\frac{1}{n^{2}}\left...
-3
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,110
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty} \frac{n \sqrt[4]{11 n}+\sqrt{25 n^{4}-81}}{(n-7 \sqrt{n}) \sqrt{n^{2}-n+1}}$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{n \sqrt[4]{11 n}+\sqrt{25 n^{4}-81}}{(n-7 \sqrt{n}) \sqrt{n^{2}-n+1}}=\lim _{n \rightarrow \infty} \frac{\frac{1}{n^{2}}\left(n \sqrt[4]{11 n}+\sqrt{25 n^{4}-81}\right)}{\frac{1}{n^{2}}(n-7 \sqrt{n}) \sqrt{n^{2}-n+1}}= \\ & =\lim _{n \rightarrow \inft...
5
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,111
## Problem Statement Calculate the limit of the numerical sequence: $$ \lim _{n \rightarrow \infty}\left(\sqrt{\left(n^{2}+1\right)\left(n^{2}+2\right)}-\sqrt{\left(n^{2}-1\right)\left(n^{2}-2\right)}\right) $$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty}\left(\sqrt{\left(n^{2}+1\right)\left(n^{2}+2\right)}-\sqrt{\left(n^{2}-1\right)\left(n^{2}-2\right)}\right)= \\ & =\lim _{n \rightarrow \infty} \frac{\left(\sqrt{\left(n^{2}+1\right)\left(n^{2}+2\right)}-\sqrt{\left(n^{2}-1\right)\left(n^{2}-2\right)}\right...
3
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,112
## Task Condition Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty} \frac{1+2+\ldots+n}{n-n^{2}+3}$
## Solution $$ \begin{aligned} & \lim _{n \rightarrow \infty} \frac{1+2+\ldots+n}{n-n^{2}+3}=\lim _{n \rightarrow \infty} \frac{\frac{(1+n) n}{2}}{n-n^{2}+3}= \\ & =\lim _{n \rightarrow \infty} \frac{n+n^{2}}{2\left(n-n^{2}+3\right)}=\lim _{n \rightarrow \infty} \frac{\frac{1}{n^{2}}\left(n+n^{2}\right)}{\frac{1}{n^{2...
-\frac{1}{2}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,113
## Problem Statement Calculate the limit of the numerical sequence: $\lim _{n \rightarrow \infty}\left(\frac{3 n^{2}-5 n}{3 n^{2}-5 n+7}\right)^{n+1}$
## Solution $\lim _{n \rightarrow \infty}\left(\frac{3 n^{2}-5 n}{3 n^{2}-5 n+7}\right)^{n+1}=\lim _{n \rightarrow \infty}\left(\frac{3 n^{2}-5 n+7}{3 n^{2}-5 n}\right)^{-n-1}=$ $=\lim _{n \rightarrow \infty}\left(1+\frac{7}{3 n^{2}-5 n}\right)^{-n-1}=\lim _{n \rightarrow \infty}\left(1+\frac{1}{\left(\frac{3 n^{2}-5...
1
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,114
## Condition of the problem Prove that (find $\delta(\varepsilon)$ : $$ \lim _{x \rightarrow-7} \frac{2 x^{2}+15 x+7}{x+7}=-13 $$
## 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_ae19746d5d2a92572015g-04.jpg?height=74&width=1483&top_left...
\delta(\varepsilon)=\frac{\varepsilon}{2}
Calculus
proof
Yes
Yes
olympiads
false
47,115
## Condition of the problem Prove that the function $f(x)_{\text {is continuous at the point }} x_{0}$ (find $\delta(\varepsilon)$ ): $f(x)=-2 x^{2}-4, x_{0}=3$
## Solution By definition, the function $f(x)_{\text {is continuous at the point }} x=x_{0}$, if $\forall \varepsilon>0: \exists \delta(\varepsilon)>0:$. $\left|x-x_{0}\right|0_{\text {there exists such }} \delta(\varepsilon)>0$, that $\left|f(x)-f\left(x_{0}\right)\right|<\varepsilon_{\text {when }}$ $\left|x-x_{0}\r...
proof
Calculus
proof
Yes
Yes
olympiads
false
47,116
Condition of the problem Calculate the limit of the function: $$ \lim _{x \rightarrow-1} \frac{x^{3}-3 x-2}{x^{2}+2 x+1} $$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow-1} \frac{x^{3}-3 x-2}{x^{2}+2 x+1}=\left\{\frac{0}{0}\right\}=\lim _{x \rightarrow-1} \frac{(x+1)\left(x^{2}-x-2\right)}{(x+1)^{2}}= \\ & =\lim _{x \rightarrow-1} \frac{x^{2}-x-2}{x+1}=\left\{\frac{0}{0}\right\}=\lim _{x \rightarrow-1} \frac{(x+1)(x-2)}{x+1}= \\ & ...
-3
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,117
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow \frac{1}{4}} \frac{\sqrt[3]{\frac{x}{16}}-\frac{1}{4}}{\sqrt{\frac{1}{4}+x}-\sqrt{2 x}}$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow \frac{1}{4}} \frac{\sqrt[3]{\frac{x}{16}}-\frac{1}{4}}{\sqrt{\frac{1}{4}+x}-\sqrt{2 x}}=\lim _{x \rightarrow \frac{1}{4}} \frac{\left(\sqrt[3]{\frac{x}{16}}-\frac{1}{4}\right)\left(\sqrt[3]{\left(\frac{x}{16}\right)^{2}}+\sqrt[3]{\frac{x}{16}} \cdot \frac{1}{4}+\le...
-\frac{2}{3}\sqrt{\frac{1}{2}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,118
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0} \frac{1-\sqrt{\cos x}}{x \cdot \sin x}$
## Solution Let's use the substitution of equivalent infinitesimals: $1-\cos x \sim \frac{x^{2}}{2}$, as $x \rightarrow 0$ $\sin x \sim x$, as $x \rightarrow 0$ We get: $$ \begin{aligned} & \lim _{x \rightarrow 0} \frac{1-\sqrt{\cos x}}{x \cdot \sin x}=\left\{\frac{0}{0}\right\}=\lim _{x \rightarrow 0} \frac{(1-\s...
\frac{1}{4}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,119
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 2} \frac{1-2^{4-x^{2}}}{2\left(\sqrt{2 x}-\sqrt{3 x^{2}-5 x+2}\right)} $$
## Solution Substitution: $x=y+2 \Rightarrow y=x-2$ $x \rightarrow 2 \Rightarrow y \rightarrow 0$ We get: $$ \begin{aligned} & \lim _{x \rightarrow 2} \frac{1-2^{4-x^{2}}}{2\left(\sqrt{2 x}-\sqrt{3 x^{2}-5 x+2}\right)}= \\ & =\lim _{y \rightarrow 0} \frac{1-2^{4-(y+2)^{2}}}{2\left(\sqrt{2(y+2)}-\sqrt{3(y+2)^{2}-5(...
-\frac{8\ln2}{5}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,120
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 1} \frac{\sqrt{2^{x}+7}-\sqrt{2^{x+1}+5}}{x^{3}-1} $$
## Solution Substitution: $$ \begin{aligned} & x=y+1 \Rightarrow y=x-1 \\ & x \rightarrow 1 \Rightarrow y \rightarrow 0 \end{aligned} $$ We get: $$ \begin{aligned} & \lim _{x \rightarrow 1} \frac{\sqrt{2^{x}+7}-\sqrt{2^{x+1}+5}}{x^{3}-1}=\lim _{y \rightarrow 0} \frac{\sqrt{2^{y+1}+7}-\sqrt{2^{(y+1)+1}+5}}{(y+1)^{3}...
-\frac{\ln2}{9}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,121
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 0} \frac{4^{5 x}-9^{-2 x}}{\sin x-\tan x^{3}} $$
## Solution $$ \begin{aligned} & \lim _{x \rightarrow 0} \frac{4^{5 x}-9^{-2 x}}{\sin x-\operatorname{tg} x^{3}}=\lim _{x \rightarrow 0} \frac{\left(1024^{x}-1\right)-\left(81^{-x}-1\right)}{\sin x-\operatorname{tg} x^{3}}= \\ & =\lim _{x \rightarrow 0} \frac{\left(\left(e^{\ln 1024}\right)^{x}-1\right)-\left(\left(e^...
\ln(2^{10}\cdot9^{2})
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,122
## Problem Statement Calculate the limit of the function: $\lim _{h \rightarrow 0} \frac{a^{x+h}+a^{x-h}-2 a^{x}}{h}$
Solution $\lim _{h \rightarrow 0} \frac{a^{x+h}+a^{x-h}-2 a^{x}}{h}=\lim _{h \rightarrow 0} \frac{a^{x+h}-a^{x}+a^{x-h}-a^{x}}{h}=$ $=\lim _{h \rightarrow 0} \frac{a^{x+h}-a^{x}}{h}+\lim _{h \rightarrow 0} \frac{a^{x-h}-a^{x}}{h}=$ $=\lim _{h \rightarrow 0} \frac{a^{x}\left(a^{h}-1\right)}{h}+\lim _{h \rightarrow 0}...
0
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,123
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0}\left(6-\frac{5}{\cos x}\right)^{\operatorname{ctg}^{2} x}$
## Solution $\lim _{x \rightarrow 0}\left(6-\frac{5}{\cos x}\right)^{\operatorname{ctg}^{2} x}=\lim _{x \rightarrow 0}\left(e^{\ln \left(6-\frac{5}{\cos x}\right)}\right)^{\frac{1}{\operatorname{tg}^{2} x}}=$ $$ =\lim _{x \rightarrow 0} e^{\ln \left(6-\frac{5}{\cos x}\right) / \operatorname{tg}^{2} x}=\exp \left\{\li...
e^{-\frac{5}{2}}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,124
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 0}\left(\frac{\ln \left(1+x^{2}\right)}{x^{2}}\right)^{\frac{3}{x+8}}$
## Solution $\lim _{x \rightarrow 0}\left(\frac{\ln \left(1+x^{2}\right)}{x^{2}}\right)^{\frac{3}{x+8}}=\left(\lim _{x \rightarrow 0} \frac{\ln \left(1+x^{2}\right)}{x^{2}}\right)^{\lim _{x \rightarrow 0} \frac{3}{x+8}}=$ $=\left(\lim _{x \rightarrow 0} \frac{\ln \left(1+x^{2}\right)}{x^{2}}\right)^{\frac{3}{0+8}}=\le...
1
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,125
## Problem Statement Calculate the limit of the function: $\lim _{x \rightarrow 2}\left(2 e^{x-2}-1\right)^{\frac{3 x+2}{x-2}}$
## Solution $\lim _{x \rightarrow 2}\left(2 e^{x-2}-1\right)^{\frac{3 x+2}{x-2}}=\lim _{x \rightarrow 2}\left(e^{\ln \left(2 e^{x-2}-1\right)}\right)^{\frac{3 x+2}{x-2}}=$ $=\lim _{x \rightarrow 2} e^{\frac{3 x+2}{x-2} \cdot \ln \left(2 e^{x-2}-1\right)}=\exp \left\{\lim _{x \rightarrow 2} \frac{3 x+2}{x-2} \cdot \ln ...
e^{16}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,126
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 1}\left(\ln ^{2} e x\right)^{\frac{1}{x^{2}+1}} $$
## Solution $$ \lim _{x \rightarrow 1}\left(\ln ^{2} e x\right)^{\frac{1}{x^{2}+1}}=\left(\ln ^{2}(e \cdot 1)\right)^{\frac{1}{1^{2}+1}}=\left(1^{2}\right)^{\frac{1}{2}}=1 $$ ## Problem Kuznetsov Limits 20-21
1
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,127
## Problem Statement Calculate the limit of the function: $$ \lim _{x \rightarrow 0} \ln \left(\left(e^{x^{2}}-\cos x\right) \cos \left(\frac{1}{x}\right)+\tan\left(x+\frac{\pi}{3}\right)\right) $$
## Solution Since $\cos \left(\frac{1}{x}\right)_{\text {- is bounded, and }}$ $$ \begin{aligned} & \lim _{x \rightarrow 0} e^{x^{2}}-\cos x=e^{0^{2}}-\cos 0=e^{0}-1=1-1=0 \\ & \left(e^{x^{2}}-\cos x\right) \cos \left(\frac{1}{x}\right) \rightarrow 0, \text { then } \\ & \text {, as } x \rightarrow 0 \end{aligned} $$...
\ln\sqrt{3}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,128
## Problem Statement Write the decomposition of vector $x$ in terms of vectors $p, q, r$: $x=\{-5 ; 9 ;-13\}$ $p=\{0 ; 1 ;-2\}$ $q=\{3 ;-1 ; 1\}$ $r=\{4 ; 1 ; 0\}$
## Solution The desired decomposition of vector $x$ is: $x=\alpha \cdot p+\beta \cdot q+\gamma \cdot r$ Or in the form of a system: $$ \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...
5p-3q+r
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,129
## Problem Statement Are the vectors $c_{1 \text { and }} c_{2}$, constructed from vectors $a \text{ and } b$, collinear? $a=\{1 ;-2 ; 4\}$ $b=\{7 ; 3 ; 5\}$ $c_{1}=6 a-3 b$ $c_{2}=b-2 a$
## 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 $c_{1}=-3(b-2 a)=-3 c_{2}$ for any $a$ and $b$. That is, $c_{1}=-3 \cdot c_{2}$, which means the vectors $c_{1}...
c_{1}=-3\cdotc_{2}
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,130
## Problem Statement Find the cosine of the angle between vectors $\overrightarrow{A B}$ and $\overrightarrow{A C}$. $A(1, -1, 0), B(-2, -1, 4), C(8, -1, -1)$
## Solution Let's find $\overrightarrow{A B}$ and $\overrightarrow{A C}$: $$ \begin{aligned} & \overrightarrow{A B}=(-2-1 ;-1-(-1) ; 4-0)=(-3 ; 0 ; 4) \\ & \overrightarrow{A C}=(8-1 ;-1-(-1) ;-1-0)=(7 ; 0 ;-1) \end{aligned} $$ We find the cosine of the angle $\phi$ between the vectors $\overrightarrow{A B}$ and $\ov...
-\frac{1}{\sqrt{2}}
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,131
## Task Condition Calculate the area of the parallelogram constructed on vectors $a$ and $b$. $a=10 p+q$ $b=3 p-2 q$ $|p|=4$ $|q|=1$ $(\widehat{p, q})=\frac{\pi}{6}$
## 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=(10 p+q) \times(3 p-2 q)=10 \cdot 3 \cdot p \times p+10 \cdot(-2) \cdot p \times ...
46
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,132
## Task Condition Are the vectors $a, b$ and $c$ coplanar? $a=\{4 ; 1 ; 2\}$ $b=\{9 ; 2 ; 5\}$ $c=\{1 ; 1 ;-1\}$
## 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} 4 & 1 & 2 \\ 9 & 2 & 5 \\ 1 & 1 & -1 \end{array}\right|= \\ & =4 \cdot\left|\be...
proof
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,133
## Problem Statement Calculate the volume of the tetrahedron with vertices at points \( A_{1}, A_{2}, A_{3}, A_{4} \) and its height dropped from vertex \( A_{4} \) to the face \( A_{1} A_{2} A_{3} \). \( A_{1}(1 ; -1 ; 1) \) \( A_{2}(-2 ; 0 ; 3) \) \( A_{3}(2 ; 1 ; -1) \) \( A_{4}(2 ; -2 ; -4) \)
## Solution From vertex $A_{1 \text {, we draw vectors: }}$ $$ \begin{aligned} & \vec{A}_{1} \vec{A}_{2}=\{-2-1 ; 0-(-1) ; 3-1\}=\{-3 ; 1 ; 2\} \\ & A_{1} A_{3}=\{2-1 ; 1-(-1) ;-1-1\}=\{1 ; 2 ;-2\} \\ & \vec{A}_{1} \overrightarrow{A_{4}}=\{2-1 ;-2-(-1) ;-4-1\}=\{1 ;-1 ;-5\} \end{aligned} $$ According to the geometri...
5.5
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,134
## Problem Statement Find the distance from point $M_{0}$ to the plane passing through three points $M_{1}, M_{2}, M_{3}$. $M_{1}(-1 ; -5 ; 2)$ $M_{2}(-6 ; 0 ; -3)$ $M_{3}(3 ; 6 ; -3)$ $M_{0}(10 ; -8 ; -7)$
## Solution Find the equation of the plane passing through three points $M_{1}, M_{2}, M_{3}$: $$ \left|\begin{array}{ccc} x-(-1) & y-(-5) & z-2 \\ -6-(-1) & 0-(-5) & -3-2 \\ 3-(-1) & 6-(-5) & -3-2 \end{array}\right|=0 $$ Perform transformations: $$ \begin{aligned} & \left|\begin{array}{ccc} x+1 & y+5 & z-2 \\ -5 &...
2\sqrt{38}
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,135
## problem statement Write the equation of the plane passing through point $A$ and perpendicular to the vector $\overrightarrow{B C}$. $A(1 ; 0 ;-6)$ $B(-7 ; 2 ; 1)$ $C(-9 ; 6 ; 1)$
## Solution Let's find the vector $\overrightarrow{B C}$: $\overrightarrow{B C}=\{-9-(-7) ; 6-2 ; 1-1\}=\{-2 ; 4 ; 0\}$ Since the vector $\overrightarrow{B C}$ is perpendicular to the desired plane, it can be taken as the normal vector. Therefore, the equation of the plane will be: $$ \begin{aligned} & -2 \cdot(x-1...
-x+2y+1=0
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,136
## Task Condition Find the angle between the planes: $x-2 y+2 z+17=0$ $x-2 y-1=0$
## Solution The dihedral angle between planes is equal to the angle between their normal vectors. The normal vectors of the given planes are: $\overrightarrow{n_{1}}=\{1 ;-2 ; 2\}$ $\overrightarrow{n_{2}}=\{1 ;-2 ; 0\}$ The angle $\phi$ between the planes is determined by the formula: $$ \begin{aligned} & \cos \ph...
4148^{\}37^{\\}
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,137
## Problem Statement Find the coordinates of point $A$, which is equidistant from points $B$ and $C$. $A(0 ; y ; 0)$ $B(7 ; 3 ;-4)$ $C(1 ; 5 ; 7)$
## Solution Let's find the distances $A B$ and $A C$: $$ \begin{aligned} & A B=\sqrt{(7-0)^{2}+(3-y)^{2}+(-4-0)^{2}}=\sqrt{49+9-6 y+y^{2}+16}=\sqrt{y^{2}-6 y+74} \\ & A C=\sqrt{(1-0)^{2}+(5-y)^{2}+(7-0)^{2}}=\sqrt{1+25-10 y+y^{2}+49}=\sqrt{y^{2}-10 y+75} \end{aligned} $$ Since by the condition of the problem $A B=A ...
A(0;\frac{1}{4};0)
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,138
## Task Condition Let $k$ be the coefficient of similarity transformation with the center at the origin. Is it true that point $A$ belongs to the image of plane $a$? $A(-1 ; 2 ; 3)$ $a: x-3 y+z+2=0$ $k=2.5$
## Solution When transforming similarity with the center at the origin of the plane $a: A x+B y+C z+D=0_{\text{and coefficient }} k$ transitions to the plane $a^{\prime}: A x+B y+C z+k \cdot D=0$. We find the image of the plane $a$: $a^{\prime}: x-3 y+z+5=0$ Substitute the coordinates of point $A$ into the equatio...
1\neq0
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,139
## Task Condition Write the canonical equations of the line. $2 x+y-3 z-2=0$ $2 x-y+z+6=0$
## Solution Canonical equations of a line: $\frac{x-x_{0}}{m}=\frac{y-y_{0}}{n}=\frac{z-z_{0}}{p}$ where $\left(x_{0} ; y_{0} ; z_{0}\right)_{\text {- are coordinates of some point on the line, and }} \vec{s}=\{m ; n ; p\}$ - its direction vector. Since the line belongs to both planes simultaneously, its direction ...
\frac{x+1}{-2}=\frac{y-4}{-8}=\frac{z}{-4}
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,140
## Problem Statement Find the point of intersection of the line and the plane. $\frac{x-1}{8}=\frac{y-8}{-5}=\frac{z+5}{12}$ $x-2 y-3 z+18=0$
## Solution Let's write the parametric equations of the line. $$ \begin{aligned} & \frac{x-1}{8}=\frac{y-8}{-5}=\frac{z+5}{12}=t \Rightarrow \\ & \left\{\begin{array}{l} x=1+8 t \\ y=8-5 t \\ z=-5+12 t \end{array}\right. \end{aligned} $$ Substitute into the equation of the plane: $$ \begin{aligned} & (1+8 t)-2(8-5 ...
(9;3;7)
Algebra
math-word-problem
Yes
Yes
olympiads
false
47,141
## Problem Statement Find the point $M^{\prime}$ symmetric to the point $M$ with respect to the plane. $M(-1 ; 2 ; 0)$ $4 x-5 y-z-7=0$
## 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: $\vec{s}=\vec{n}=\{4 ;-5 ;-1\}$ Then the equation of the desired line is: $\f...
M^{\}(3;-3;-1)
Geometry
math-word-problem
Yes
Yes
olympiads
false
47,142
## problem statement Based on the definition of the derivative, find $f^{\prime}(0)$ : $$ f(x)=\left\{\begin{array}{c} \sqrt[3]{1-2 x^{3} \sin \frac{5}{x}}-1+x, x \neq 0 \\ 0, x=0 \end{array}\right. $$
## 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: $$ \begin{aligned} & f^{\prime}(0)=\lim _{\Delta x \rightarrow 0} \frac{f(0+\Delta x)-f(0)}{\Delta x}=\lim _{\Delta x \rightarrow 0} ...
1
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,143
## problem statement Find the equation of the tangent line to the given curve at the point with abscissa $x_{0}$. $y=3 \sqrt[4]{x}-\sqrt{x}, x_{0}=1$
## Solution Let's find $y^{\prime}$: $y^{\prime}=(3 \sqrt[4]{x}-\sqrt{x})^{\prime}=\left(3 x^{\frac{1}{4}}-\sqrt{x}\right)^{\prime}=3 \cdot \frac{1}{4} \cdot x^{-\frac{3}{4}}-\frac{1}{2 \sqrt{x}}=\frac{3}{4 \sqrt[4]{x^{3}}}-\frac{1}{2 \sqrt{x}}$ Then $y_{0}^{\prime}=y^{\prime}\left(x_{0}\right)=\frac{3}{4 \sqrt[4]{...
\frac{x}{4}+\frac{7}{4}
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,144
## Condition of the problem Find the differential $d y$. $$ y=\cos x \cdot \ln (\operatorname{tg} x)-\ln \left(\operatorname{tg} \frac{x}{2}\right) $$
## Solution $$ \begin{aligned} & d y=y^{\prime}(x) \cdot \Delta x=y^{\prime}(x) \cdot d x \\ & y^{\prime}=(\cos x)^{\prime} \cdot \ln \operatorname{tg} x+\cos x \cdot(\ln \operatorname{tg} x)^{\prime}-\left(\operatorname{lntg} \frac{x}{2}\right)^{\prime}= \\ & =-\sin x \cdot \ln \operatorname{tg} x+\cos x \cdot \frac{...
-\sinx\cdot\ln\operatorname{tg}x\cdot
Calculus
math-word-problem
Yes
Yes
olympiads
false
47,145