Question

Let f(x) = 3x^2 + 5x – 7 and g(x) = –x^2 + 2x + 1. (g-f) (3)

Answer 1

- 37

Explanation:

Note (g - f)(x) = g(x) - f(x)

g(x) - f(x)

= - x² + 2x + 1 - ( 3x² + 5x - 7) ← distribute

= - x² + 2x + 1 - 3x² - 5x + 7 ← collect like terms

= - 4x² - 3x + 8

Thus

(g - f)(3) = - 4(3)² - 3(3) + 8 = - 4(9) - 9 + 8 = - 36 - 9 + 8 = - 37

Answer 2

Solution given:

f(x) = 3x^2 + 5x – 7

g(x) = –x^2 + 2x+1

Explanation:

now

(g-f)(x)=g(x)-f(x)=–x^2 + 2x + 1.-[3x^2 + 5x – 7]

=x²-3x²-5x+2x+1+7

=-2x²-3x+8

now.

(g-f)(3)=-2×3²-3×3+8=-18-9+8=-19

is your answer.