Please help prove the following:

Problem 2.3 Consider a point mass m moving at velocity v(t) with position "(t) defined by some origin. Its angular momentum relative to that origin is therefore J = T X P with p = mv. Derive (2.14) by taking the time derivative of this angular momentum. Note (2.2) and (2.3). dj = N (2.14) dt F = dp (2.2) dt dN = FX dF 2.3