;

Set up the composite result function.

Evaluate by substituting in the value of into .

Rewrite as .

Expand using the FOIL Method.

Apply the distributive property.

Apply the distributive property.

Apply the distributive property.

Simplify and combine like terms.

Simplify each term.

Multiply by .

Multiply by .

Multiply by .

Multiply by .

Multiply by .

Add and .

Subtract from .

Find f(g(x)) f(x)=x^2-4 ; g(x)=2x+1