Find f(g(x)) f(x)=3x-5 , g(x)=4x^2-5

$f (x) = 3 x - 5$ , $g (x) = 4 x^{2} - 5$

Step 1

Set up the composite result function.

$f (g (x))$

Step 2

Evaluate $f (4 x^{2} - 5)$ by substituting in the value of $g$ into $f$ .

$f (4 x^{2} - 5) = 3 (4 x^{2} - 5) - 5$

Step 3

Simplify each term.

Apply the distributive property.

$f (4 x^{2} - 5) = 3 (4 x^{2}) + 3 \cdot - 5 - 5$

Multiply $4$ by $3$ .

$f (4 x^{2} - 5) = 12 x^{2} + 3 \cdot - 5 - 5$

Multiply $3$ by $- 5$ .

$f (4 x^{2} - 5) = 12 x^{2} - 15 - 5$

Step 4

Subtract $5$ from $- 15$ .

$f (4 x^{2} - 5) = 12 x^{2} - 20$