Find the derivative of f(x)=x2(x+1)f(x) = x^2(x + 1)f(x)=x2(x+1) by expanding first.
3x2+2x3x^2 + 2x3x2+2x
x2+2xx^2 + 2xx2+2x
3x23x^23x2
2x(x+1)2x(x+1)2x(x+1)