\(\left(\dfrac{1}{2}\right)^3\cdot\left[\left(\dfrac{1}{2}\right)^x\right]^x-\dfrac{5}{8}=\dfrac{1}{16}\cdot\left(-9\right)\)
\(\left(\dfrac{1}{2}\right)^3\cdot\left[\left(\dfrac{1}{2}\right)^x\right]^x-\dfrac{5}{8}=\dfrac{-9}{16}\)
\(\left(\dfrac{1}{2}\right)^3\cdot\left[\left(\dfrac{1}{2}\right)^x\right]^x=\dfrac{-9}{16}+\dfrac{5}{8}\)
\(\left(\dfrac{1}{2}\right)^3\cdot\left[\left(\dfrac{1}{2}\right)^x\right]^x=\dfrac{1}{16}\)
\(\left(\dfrac{1}{2}\right)^3\cdot\left[\left(\dfrac{1}{2}\right)^x\right]^x=\left(\dfrac{1}{2}\right)^4\)
\(\left[\left(\dfrac{1}{2}\right)^x\right]^x=\left(\dfrac{1}{2}\right)^4\div\left(\dfrac{1}{2}\right)^3\)
\(\left[\left(\dfrac{1}{2}\right)^x\right]^x=\dfrac{1}{2}\)
\(\left[\left(\dfrac{1}{2}\right)^x\right]^x=\left[\left(\dfrac{1}{2}\right)^1\right]^1\)
\(\Rightarrow x=1\)