\(\dfrac{1}{8}=\dfrac{1}{2^3}=\left(\dfrac{1}{2}\right)^3\)
\(-\dfrac{1}{27}=\dfrac{\left(-1\right)^3}{3^3}=\left(-\dfrac{1}{3}\right)^3\)
\(\dfrac{81}{16}=\dfrac{3^4}{2^4}=\left(\dfrac{3}{2}\right)^4\)
\(\dfrac{8}{125}=\dfrac{2^3}{5^3}=\left(\dfrac{2}{5}\right)^3\)
\(0,0625=\dfrac{1}{16}=\dfrac{1}{2^4}=\left(\dfrac{1}{2}\right)^4\)