Question

Given that f(x) = x^2– 5x– 36 and g(x) = x + 4, find (f +9)(x) and express

the result in standard form.

Answer 1

`\longmapsto \: f(x) = {x}^(2) - 5x - 36 \\ \longmapsto \: g(x) = x + 4 \\ \longmapsto(f + g)(x) \\ = f(x) + g(x) \\ = ( {x}^(2) - 5x - 36) + (x + 4) \\ = {x}^(2) - 5x - 36 + x + 4 \\ = \boxed{ {x}^(2) - 4x - 32}`

• x²-4x-32 (in standard form) is the right answer.

Answer 2

x^2 -4x-32

Explanation:

f(x) = x^2– 5x– 36

g(x) = x + 4

(f +g)(x) = x^2– 5x– 36 + x + 4

Combine like terms

= x^2 -4x-32