Question

If F(x)= x2+2x-3 and g(x)=x2-9 , find (f/g)(4) and(f+g)(4) .(f/g)(4) is , and (f+g)(4) is .

Answer 1

f(x) = x^2 + 2x - 3 and g(x) = x^2 - 9

(f/g)(x) = (x^2+ 2x -3) / (x^2 - 9)

(f/g)(x) = (x +3 )(x - 1) / (x + 3)(x - 3)

(f/g)(x) = (x - 1) / (x - 3)

So

(f/g)(4) = (4 - 1)/(4 -3)

(f/g)(4) =3/1

(f/g)(4) = 3

(f+g)(x) = x^2+ 2x - 3 + x^2 - 9

(f+g)(x) = 2x^2 + 2x - 12

(f+g)(x) = 2(4)^2 + 2(4) - 12

(f+g)(4) = 32 + 8 - 12

(f+g)(4) = 28