composite functions:

Question

find:

(f/g)(4)

when given:

f(x)=7x²+8

g(x)=-2x+13

Answer 1

f(x) = 7x² + 8

g(x) = -2x + 13

Divide the two polynomials. Both polynomials are already simplified. From there, substitute 1/4 for x in both functions to evaluate.

(f/g)(1/4) = [7(1/4)² + 8] / [-2(1/4) + 13]

= [7(1/16) + 8] / (-1/2 + 13)

= [(7/16) + (128/16)] / (-1/2 + 26/2)

= (135/16) / (25/2)

= (135/16)*(2/25)

= 270/400

= 27/40