Answer:
= -x^2 -10x-26
Explanation:
f(g(x) means put g(x) in for x in the function f(x)
f(x) = -x^(2)-1
f(g(x) = -(g(x))^2-1
We know g(x) = (x+5)
so substitute it in
f(g(x) = -(x+5)^2-1
FOIL
f(g(x) = -(x+5)(x+5)-1
=- (x^2 +5x+5x+25) -1
-(x^2 +10x+25) -1
Distribute the -1
= -x^2 -10x-25-1
= -x^2 -10x-26