Question

F(x)=x+1 and g(x)=x^3 -1Find (fg)(5)

Answer 1

`(fg)(x)=f(x)* g(x)`

So

`\begin{gathered} f(5)=5+1=6 \\ g(5)=5^3-1=125-1=124 \end{gathered}`

and

`\begin{gathered} (fg)(5)=f(5)* g(5) \\ (fg)(5)=6*124=744 \end{gathered}`

Answer: (fg)(5) = 744