If f(x)=2x+5 and g(x)=x^2-3, find [f*g](x)

So, [f*g](x) = f(x) * g(x)  =

[2x + 5] * [x^2 - 3] =

(2x)*(x^2) = 2x^3

(5)*(x^2) = 5x^2

(2x) * (-3) = -6x

(5)*(-3) = -15

So, putting this all together, we have

2x^3 + 5x^2 - 6x - 15   = [f*g](x)