Precalculus Examples

Given $f (x) = 2 x$ and $g (x) = x^{2} + 3$ ; find $f (g (x))$

Step 1

Set up the composite result function.

$f (g (x))$

Step 2

Evaluate $f (x^{2} + 3)$ by substituting in the value of $g$ into $f$ .

$f (x^{2} + 3) = 2 (x^{2} + 3)$

Step 3

Apply the distributive property.

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

Step 4

Multiply $2$ by $3$ .

$f (x^{2} + 3) = 2 x^{2} + 6$