The solution is already GIVEN to you!only very recently learned the chain rule and product rule but never seen a question like this usually only questions in form secx(x^2+1)^3 or something, im really just confused with the whole thing. the question initially gives you d^2/dx^2 (y^2) but usually, id see dy/dx (y), given y or higher derivatives of that... I'm not really sure where to start with the question.