p2n DO 2n + 1 Given e te * = 2 which of the O n=0 (2n)! n=0 (2n + 1)! following is the power series of er - e-? 2n + 1 O (2n + 1)! 2n - 1 O n=1 2n(2n)! 2n + 1 O IM (2n + 1)