Jika \( f(x) = 2x+1 \) maka \( f^{-1}(2) = \cdots \)
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Pembahasan:
\begin{aligned} f(x) = 2x+1 \Leftrightarrow y &= 2x+1 \\[8pt] 2x &= y-1 \\[8pt] x &= \frac{y-1}{2} \\[8pt] f^{-1}(x) &= \frac{x-1}{2} \\[8pt] f^{-1}(2) &= \frac{2-1}{2} = \frac{1}{2} \end{aligned}
Jawaban A.