Tìm x biết :a. \(\frac{{ - 11}}{{12}}x + 0,25 = \frac{5}{6}\)b. \({\left( {x - 1} \right)^5} =  - 32\)c. \(\left( {{2^3}:4} \right){.

* Hướng dẫn giải

\(\begin{array}{l}
a)\frac{{ - 11}}{{12}}x + 0,25 = \frac{5}{6} \Rightarrow \frac{{ - 11}}{{12}}x = \frac{5}{6} - 0,25 = \frac{5}{6} - \frac{1}{4} = \frac{{10 - 3}}{{12}} = \frac{7}{{12}}\\
 \Rightarrow x = \frac{7}{{12}}:\frac{{ - 11}}{{12}} = \frac{{ - 7}}{{11}}
\end{array}\)

\(\begin{array}{l}
b){\left( {x - 1} \right)^5} =  - 32 = {\left( { - 2} \right)^5}\\
 \Rightarrow x - 1 =  - 2 \Rightarrow x =  - 1
\end{array}\)

\(\begin{array}{l}
c)\left( {{2^3}:4} \right){.2^{\left( {x + 1} \right)}} = 64\\
 \Rightarrow {2.2.2^x} = 64\\
 \Rightarrow {2^x} = 16\\
 \Rightarrow x = 4
\end{array}\)

\(\begin{array}{l}
d)|3 - 2x| - 3 =  - \left( { - 3} \right) \Rightarrow |3 - 2x| - 3 = 3\\
 \Rightarrow |3 - 2x| = 6 \Rightarrow \left[ \begin{array}{l}
3 - 2x = 6\\
3 - 2x =  - 6
\end{array} \right. \Rightarrow \left[ \begin{array}{l}
 - 2x = 3\\
 - 2x =  - 9
\end{array} \right. \Rightarrow \left[ \begin{array}{l}
x = \frac{{ - 3}}{2}\\
x = \frac{9}{2}
\end{array} \right.
\end{array}\)