let g(x)=2x and h(x)=x^2+4 when (h*g)(-2)

Answer 1

(h*g)(x) = h(x)*g(x)
So, just plug in x = -2:
((-2)^2+4)*(2(-2)) = (8)*(-4) = -32

or, more generally,

(h*g)(x) = (x^2+4)(2x) = 2x^3 + 8x
so (h*G)(-2) = 2(-8)+8(-2) = -32