Home > PC3 > Chapter 1 > Lesson 1.2.2 > Problem1-85

1-85.

Given $f(x)=x^2+2x$ and $g(x)=\sqrt{x+1}$, evaluate each of the following composite function operations.

1. $g(x-2)$

Replace every $x$ in the $g$ function with the expression $(x−2)$. Then simplify.

1. $f(g(8))$

Compute $g(8)$ first. Then replace every $x$ in the $f$ function with the value of $g(8)$. Simplify.

1. $g(f(8))$

Compute $f(8)$ first. Then replace every $x$ in the $g$ function with the value of $f(8)$. Simplify.

1. $f(f(1))$

Compute $f(1)$ first. Then replace every $x$ in the $f$function with the value of $f(1)$. Simplify.

$f(3)=15$

1. $f(x+1)$

$f(x+1)=(x+1)^2+2(x+1)$

1. $g(f(x))$

$g(x^2+2x)=\sqrt{(x^2+2x)+1}$