b/ \(2^x=32^5.64^6\)
\(\Rightarrow2^x=\left(2^5\right)^5.\left(2^6\right)^6\)
\(\Rightarrow2^x=2^{25}.2^{36}\)
\(\Rightarrow2^x=2^{25+36}\)
\(\Rightarrow2^x=2^{61}\)
\(\Rightarrow x=61\)
Vậy \(x=61\)
c/ \(\left(\frac{1}{5}\right)^x=\left(\frac{1}{125}\right)^3\)
\(\Rightarrow\left(\frac{1}{5}\right)^x=\left(\frac{1^3}{5^3}\right)^3\)
\(\Rightarrow\left(\frac{1}{5}\right)^x=\left(\frac{1}{5}\right)^9\)
\(\Rightarrow x=9\)
Vậy x = 9