If f(x) = x + 4 and g(x) = x ^ 2 - 1 , what is big(g f big) big(x big) ?
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Given
[tex]\begin{gathered} f\mleft(x\mright)=x+4 \\ g\left(x\right)=x^2-1 \end{gathered}[/tex]Find
[tex](g\circ f)(x)[/tex]
Explanation
[tex]\begin{gathered} (g\circ f)(x)=g(f(x)) \\ (g\circ f)(x)=g(x+4) \\ (g\circ f)(x)=(x+4)^2-1 \\ (g\circ f)(x)=x^2+16+8x-1 \\ (g\circ f)(x)=x^2+8x+15 \end{gathered}[/tex]Final Answer
Therefore , the correct option is C.