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Decide whether or not the functions are inverses of each other.f(x) = x^3 - 3, g(x) = ^3sqrt x+3

User Tom Klino
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1 Answer

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Given the functions:


\begin{gathered} f\mleft(x\mright)=x^3-3 \\ g\mleft(x\mright)=^3\sqrt[]{x+3} \end{gathered}

The functions are inverses of each other when:


(f\circ g)(x)=x

so, we will find (fog)(x) and compare the result with the previous condition

So, We will substitute the function g(x) into the function f(x) instead of (x)


\begin{gathered} (f\circ g)(x)=(^3\sqrt[]{x+3})^3-3 \\ \end{gathered}

simplify the function:


\begin{gathered} (f\circ g)(x)=(x+3)-3 \\ (f\circ g)(x)=x+3-3 \\ \\ (f\circ g)(x)=x \end{gathered}

So, the final result is the same as the condition

so, the answer will be:

The functions are inverses of each other.

User Shaveenk
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