## cherrilyn 5 years ago determine convergence of divergence using any method..

1. cherrilyn

$\sum_{n=1}^{\infty} (-1)^{n+1} / (2n+1)!$

2. cherrilyn

absolute value method right!?

3. cherrilyn

or should I compare to 1/2n

4. watchmath

Whenever you have that (-1)^n expression, usually either you consider the absolute series or you use the alternating series (Leibniz) test.