Find g(f(x)) f(x)=x^2+x-1 g(x)=-3x+12

$f (x) = x^{2} + x - 1$ $g (x) = - 3 x + 12$

Step 1

Set up the composite result function.

$g (f (x))$

Step 2

Evaluate $g (x^{2} + x - 1)$ by substituting in the value of $f$ into $g$ .

$g (x^{2} + x - 1) = - 3 (x^{2} + x - 1) + 12$

Step 3

Simplify each term.

Apply the distributive property.

$g (x^{2} + x - 1) = - 3 x^{2} - 3 x - 3 \cdot - 1 + 12$

Multiply $- 3$ by $- 1$ .

$g (x^{2} + x - 1) = - 3 x^{2} - 3 x + 3 + 12$

Step 4

Add $3$ and $12$ .

$g (x^{2} + x - 1) = - 3 x^{2} - 3 x + 15$