`(x-1/8)^3 = -8/125`
`=>(x-1/8)^3 = (-2/5)^3
`=> x-1/8 = -2/5`
`=> x = -11/40`
\(\left(x-\dfrac{1}{8}\right)^3=\dfrac{-8}{125}\\
\Rightarrow\left(x-\dfrac{1}{8}\right)^3=\left(\dfrac{-2}{5}\right)^3\\
\Rightarrow x-\dfrac{1}{8}=\dfrac{-2}{5}\\
\Rightarrow x=\dfrac{-2}{5}+\dfrac{1}{8}\\
\Rightarrow x=-\dfrac{11}{40}\)
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