Question

If p(x)=2x^2-4 and q(x)=x-3, what is (poq)(x)

Answer 1

2x^2 -12x+14

Explanation:

(poq)(x)=

p(q(x))

Substitute q(x) in for x in the function p(x)

p(x)=2x^2-4

p(q(x)) = 2* q(x)^2-4

= 2(x-3)^2 -4

FOIL

= 2( (x-3) (x-3) -4

=2( x^2 -3x-3x+9) -4

=2 (x^2 -6x+9) -4

Distribute

=2x^2 -12x +18 -4

Combine like terms

=2x^2 -12x+14