If f(x) =4^x -8 and g(x) = 5x + 6, find (f-g)(x)

Question

If f(x) = 4^x - 8 and g(x) = 5x + 6, find (f - g)(x).

A. (f-g)(x) = 4^x +5x -2

B. (f-g)(x) = -4^x +5x +14

C. (f-g)(x) = 4^x -5x -14

D. (f-g)(x) = -x -14

Answer 1

It really is that simple.

(f - g)(x) = 4^x - 8 - (5x + 6) = 4^x - 8 - 5x - 6 = 4^x -5x - 14

C

Answer 2

If f(x) = 4^x - 8 and g(x) = 5x + 6 then f(x) - g(x) [aka f-g(x)] is

(4^x - 8) - (5x + 6) = 4^x - 8 - 5x - 6 = 4^x - 5x - 14 (which is answer C)