Find an expression for the general term of each of the series below. Use $n$ as your index, and pick your general term so that the sum giving the series starts with $n=0$.

A. $x^{2} \cos x^2 = x^{2} - {x^{6}\over 2!} + {x^{10}\over 4!} - {x^{14}\over 6!} + \cdots$
general term =

B. $x^{2} \sin x^2 = x^{4} - {x^{8}\over 3!} + {x^{12}\over 5!} - {x^{16}\over 7!} + \cdots$
general term =