Question

Given the following functions, find and simplify (f- g) (8.5).

f(x) = -x +3
g(x) = -10x - 9

Answer 1

Explanation:

an arithmetic operation (like "-") on functions is the same as using the same operation on the functional excursions themselves.

(f - g)(x) = -x + 3 - (-10x - 9) = -x + 3 + 10x + 9 =

= 9x + 12

(f - g)(8.5) = 9×8.5 + 12 = 76.5 + 12 = 88.5