find the second derivative $(x^3+x-1)(x^3+1)$ $$(x^3+x-1)(x^3+1)$$
$$=x^6+x^4-x^3+x^3+x-1$$
$$f'(x)= 6x^5+4x^3-3x^2+3x^2+1$$
Am I suppose to cancel out $-3x^2+3x^2$?
$$f''(x)= 30x^4+12x^2-6x+6x$$
Can someone check my work please? Thank you so much!

You can cancel the 6x, but yes, that is correct according to wolfram alpha.
