Question

If f(x)=3x-4 and g(x)=9x^2-16,find (fofof)(1)

Answer 1

Given:

`\begin{gathered} f(x)=3x-4 \\ g(x)=9x^2-16 \end{gathered}`

Sol:.

`\text{ The value of (}fofof)(1)`

`\begin{gathered} f(x)=3x-4 \\ (f\circ f)(x)=3(3x-4)-4 \\ (f\circ f)(x)=9x-12-4 \\ (f\circ f)(x)=9x-16 \end{gathered}`

`\begin{gathered} (f\circ f)(x)=9x-16 \\ (f\circ f\circ f)(x)=9(3x-4)-16 \\ (f\circ f\circ f)(x)=24x-36-16 \\ (f\circ f\circ f)(x)=24x-52 \end{gathered}`

`\begin{gathered} (f\circ f\circ f)(x)=24x-52 \\ (f\circ f\circ f)(1)=24(1)-52 \\ =24-52 \\ =-28 \end{gathered}`