So just a small question here, basically, are we allowed to use, and/or get marks for questions if we use calculus in the moving about graphs topic? for example, imagine they give you a displacement/time graph of a car, and it has a perfect parabolic path (or the question also gave you an equation for the motion, although I doubt they will). Lets say they want you to find the instantaneous velocity/acceleration at t=5 (or whatever). Instead of drawing a tangent there and calculating it's gradient (i always get that inaccurately), are we allowed to use differentiation to find it? are we able to get marks that way? or should we only use the traditional way?