Answer:
1. (x^3+7x^2+8x-16) ; domain: R (all real number)
2. (x-1) ; domain: R-(-4) {all real number except (-4)
Explanation:
f*g= f(x) and g(x)
i.e, f*g= (x^2+3x-4)(x+4)
i.e, f*g= x^3+3x^2-4x+4x^2+12x-16
i.e, f*g=x^3+7x^2+8x-16
it's domain is R, i.e, all real number!
f/g=(x^2+3x-4)/(x+4)
i.e, f/g={(x+4)(x-1)}/4
i.e,f/g=x-1
it's domain is all real number,except the number at which (x+4) becomes 0, i.e, x= (-4), -4 is not in domain!
✌️;)