Question

Let f(x)=x+4 and g(x)=x^2+8x –3. Find each of the following functions:
a.(f+g)(x) x^2+(x+8x)+(4-3) X^2+9x+1
b.(f –g)(x) x+4 - (x^2 + 8x - 3) = x + 4 -x^2 - 8x + 3= -x^2 -7x+7
c.(fg)(x) (x+4)(x^2 + 8x - 3
d.f*g
[Hint: f(g(x) )]
I need help with D please