Решите пожалуйста неравенства:

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Решите пожалуйста неравенства:


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Алгебра (1.4k баллов) | 20 просмотров
Дано ответов: 2
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Правильный ответ

А) ОТВЕТ: \mathtt{x\in(1;\frac{11}{3})}

\mathtt{\log_3^2(4-x)-1\ \textless \ 0;~(\log_3(4-x)-1)(\log_3(4-x)+1)\ \textless \ 0;~}\\\mathtt{-1\ \textless \ \log_3(4-x)\ \textless \ 1;~\frac{1}{3}\ \textless \ 4-x\ \textless \ 3;~-3\ \textless \ x-4\ \textless \ -\frac{1}{3};~1\ \textless \ x\ \textless \ \frac{11}{3}}

б) ОТВЕТ: \mathtt{x\in(\frac{1}{125};\frac{1}{25})}

\mathtt{\log_{0,2}^2x-5\log_{0,2}x\ \textless \ -6;~\log_5^2x+5\log_5x+6\ \textless \ 0;~}\\\mathtt{(\log_5x+3)(\log_5x+2)\ \textless \ 0;~-3\ \textless \ \log_5x\ \textless \ -2;~\frac{1}{5^3}\ \textless \ x\ \textless \ \frac{1}{5^2}}

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(1)
log_3^2(4-x)\ \textless \ 1\\\\
log_3^2(4-x)-1^2\ \textless \ 0\\\\
(log_3(4-x)+1)*(log_3(4-x)-1)\ \textless \ 0\\\\
-1\ \textless \ log_3(4-x)\ \textless \ 1\\\\
\begin{equation*}
\begin{cases}
log_3(4-x)\ \textgreater \ -1\\
log_3(4-x)\ \textless \ 1
\end{cases}
\end{equation*}\\\\
\begin{equation*}
\begin{cases}
log_3(4-x)\ \textgreater \ log_3(3^{-1})\\
log_3(4-x)\ \textless \ log_3(3)
\end{cases}
\end{equation*}
\begin{equation*}
\begin{cases}
4-x\ \textgreater \ \frac{1}{3}\\
4-x\ \textless \ 3\\
 4-x\ \textgreater \ 0
\end{cases}
\end{equation*}

\begin{equation*}
\begin{cases}
x\ \textless \ \frac{11}{3}\\
x\ \textgreater \ 1\\
 x\ \textless \ 4
\end{cases}
\end{equation*}

x\in(1;\ \frac{11}{3})
---------------------------------------
(2)
log_{0.2}^2(x)-5*log_{0.2}(x)\ \textless \ -6\\\\
log_{0.2}^2(x)-5*log_{0.2}(x)+6\ \textless \ 0\\\\
(log_{0.2}(x)-2)*(log_{0.2}(x)-3)\ \textless \ 0\\\\
2\ \textless \ log_{0.2}(x)\ \textless \ 3\\\\
2\ \textless \ log_{5^{-1}}(x)\ \textless \ 3\\\\
2\ \textless \ -log_{5}}(x)\ \textless \ 3\\\\
 \left \{ {{log_{5}}(x)\ \textless \ -2} \atop {log_{5}}(x)\ \textgreater \ -3}} \right. ;\\\\
 \left \{ {{log_{5}}(x)\ \textless \ log_5(5^{-2})} \atop {log_{5}}(x)\ \textgreater \ log_5(5^{-3})}} \right. \\\\
 \left \{ {{x\ \textless \ \frac{1}{25}} \atop {x\ \textgreater \ \frac{1}{125}}}\\ \atop {x\ \textgreater \ 0} \right. \\\\
x\in(\frac{1}{125}};\ \frac{1}{25}})

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