Question

Question #60966

Answer 1

`f(f(x))=x^4+2x^3+2x^2+x`

Explanation:

`f(color(red)(x)) = color(red)(x)^2+color(red)(x)`

`f(color(red)(f(x))) = (color(red)(f(x)))^2 + color(red)(f(x))`

`=(x^2+x)^2 + (x^2+x)`

`=(x^4+2x^3+x^2)+(x^2+x)`

`=x^4+2x^3+2x^2+x`