f(x)=5x+6,g(x)=3x2−4x+8. Find (f - g)(x)

Answer 1

We substitute the expressions of f(x) and g(x) into (f-g)(x) and simplify:

(f - g)(x) = [5x + 6] - [3x² - 4x +8]

= 5x +6 - 3x² + 4x - 8

= - 3x² + 9x - 2.

Note, we change the signs opening the second set of brackets and combined like terms. In addition, to make the final answer more readable, we rearranged the expression by descending exponents of the variable x.