Question

Given that f(x)=5x+9 and g(x)=9-x^2
calculate
f(g(0))
g(f(0))

Answer 1

Start from the inside and work your way out

For f(g(0)), g(0)= 9-(0^2) = 9, f(9)= 5(9)+9 = 54
So f(g(0)) = 54

For g(f(0)), f(0)= 5(0)+9 = 9, g(9)= 9-(9^2) = -72
So g(f(0)) = -72