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Given f(x)=x+2 and g(x)=4-x^2 find the following (g o f)(x)

User Dlowe
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1 Answer

26 votes
26 votes

Given functions are


\begin{gathered} f(x)=x+2 \\ g(x)=4-x^2 \end{gathered}

Then,


\begin{gathered} (g\circ f)(x)=g(f(x)) \\ =g(x+2) \\ =4-(x+2)^2 \\ =4-(x^2+4x+4) \\ =4-x^2-4x-4 \\ =-(x^2+4x) \end{gathered}

Thus,


(g\circ f)(x)=-(x^2+4x)

User Jzqa
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