\(\left(\dfrac{1}{2}\right)^{x+1}-\dfrac{1}{2}=\dfrac{-3}{8}\)
\(\left(\dfrac{1}{2}\right)^x.\dfrac{1}{2}=\dfrac{-3}{8}+\dfrac{4}{8}\)
\(\left(\dfrac{1}{2}\right)^x.\dfrac{1}{2}=\dfrac{1}{8}\)
\(\left(\dfrac{1}{2}\right)^x=\dfrac{1}{8}.2\)
\(\left(\dfrac{1}{2}\right)^x=\dfrac{1}{4}\)
\(\left(\dfrac{1}{2}\right)^x=\left(\dfrac{1}{2}\right)^2\)
\(x=2\)
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