Answer:
f(x)= x-6
g(x)= x^1/2 (x+3) =√x(x+3) = x √x + 3√x
g(x) × f(x)
=(x√x + 3√x) (x-6)
= x²√x -6x√x + 3x√x - 18√x
= x²√x -3x√x - 18 √x
= x^5/2 - 3x^3/2 - 18^1/2
= √x^5 - 3√x^3 - √18 (B)
Note:
√x = x^1/2
x √x = x^1 × √x= x^1+1/2= x^3/2
x²√x= x^2 × x^1/2 = x^2+1/2 = x^ 5/2
I hope this helps
if u have question let me know in comments ^_^