Question

Show that the following series converges absolutely:

Answer 1

\[\sum_{n=1}^{\infty}\frac{ (-1)^n }{ (n+3)^2 }\]

Answer 2

If I took the absolute value of this thing what would I exactly get?

Answer 3

converges absolutely means the absolute value of the terms converge, so show that
\[\sum_{n=1}^{\infty}\frac{1}{(n+3)^2}\] converges
you can use comparison test for this

Answer 4

Ahh. That's what I was looking for. Thanks!

Answer 5

yw