Question

Given the definitions of f(x) and g(x) below, find the value of f(g(-1)).

f(x) = x^2+ x + 10
g(x) -5x-3

Answer 1

16

Explanation:

Given the definitions of f(x) and g(x) below,

f(x) = x^2+ x + 10

g(x) = -5x-3

f(g(x)) = f(-5x-3)

f(-5x-3) = (-5x-3)²+((-5x-3)+10

f(-5x-3) = 25x²+30x+9-5x-3+10

f(-5x-3) = 25x² +25x+16

f(g(x)) = 25x² +25x+16

f(g(-1)) = 25(-1)² +25(-1)+16

f(g(-1)) = 25-25 + 16

f(g(-1)) = 16

Hence f(g(-1)) is 16