Answer:
8c
f(g(x)) = x^4 + 2x^3 - x
g(f(x)) = x^4 + 2x^3 + 2x^2 - x
Explanation:
f(x) = x^2 - x ; g(x) = x^2 + x
f(g(x)) = (x^2 + x)^2 - (x^2 + x)
f(g(x)) = (x^2 + x)^2 - x^2 - x
f(g(x)) = (x^2 + x)(x^2 + x) - x^2 - x
f(g(x)) = x^4 + x^3 + x^3 + x^2 - x^2 - x
f(g(x)) = x^4 + 2x^3 - x
g(f(x)) = (x^2 - x)^2 + x^2 - x
g(f(x)) = (x^2 + x)(x^2 + x) + x^2 - x
g(f(x)) = x^4 + x^3 + x^3 + x^2 + x^2 - x
g(f(x)) = x^4 + 2x^3 + 2x^2 - x