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Algebra Difficulty 2.8 Junior Find the answer

Given the function f(x)=2log2(2x1)f(x) = 2 \log_2 (2x - 1), find the value of f1(0)f^{-1}(0):

Pick one

Solution

To find f1(0)f^{-1}(0), we need to find the value of xx that makes f(x)=0f(x) = 0.

Step 1: Set f(x)=0f(x) = 0:
\begin{align*}
2 \log_2 (2x - 1) &= 0 \\
\log_2 (2x - 1) &= 0
\end{align*}

Step 2: Solve for xx:
\begin{align*}
2x - 1 &= 2^0 \\
2x - 1 &= 1 \\
2x &= 2 \\
x &= 1
\end{align*}

Step 3: Verify the answer:
\begin{align*}
f(1) &= 2 \log_2 (2(1) - 1) \\
&= 2 \log_2 (1) \\
&= 2 \cdot 0 \\
&= 0
\end{align*}

Thus, f1(0)=1f^{-1}(0) = \boxed{1}.

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.