Question

Given that f(x) = 4x - 7 and g(x) = 4x, find a simplified expression for
f(f(x)).

Answer 1

Given:

`f(x)=4x-7`

`g(x)=4x`

To find:

The expression for f(f(x)).

Solution:

We need to find f(f(x)).

`f(f(x))=f(4x-7)`
`[\because f(x)=4x-7]`

`f(f(x))=4(4x-7)-7`
`[\because f(x)=4x-7]`

Using distributive property, we get

`f(f(x))=4(4x)+4(-7)-7`

`f(f(x))=16x-28-7`

`f(f(x))=16x-35`

Therefore, the expression for f(f(x)) is
`f(f(x))=16x-35`.