Question

If f(x) = 2x2 and g(x)= x2 + 2x, which expression represents f(g(x))?

Answer 1

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

f(g(x)) = 2x^4 + 8x^3 + 8x^2

Explanation:

Given;

f(x) = 2x^2

g(x) = x^2 + 2x

To derive the expression for f(g(x)), we will substitute x in f(x) with g(x).

f(g(x)) = 2(g(x))^2

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

Expanding the equation;

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

f(g(x)) = 2(x^4 + 2x^3 + 2x^3 + 4x^2)

f(g(x)) = 2(x^4 + 4x^3 + 4x^2)

f(g(x)) = 2x^4 + 8x^3 + 8x^2

Hope this helps...