In this section we briefly state two results concerning series
that are not necessarily
. The first result has to do with
absolute convergence and the second with alternating series.
is said to converge absolutely if
converges. It is a theorem that if any series converges
absolutely, then it also converges.
is said to be alternating if the
between being positive and negative. If
is an alternating series
| an+1|≤| an|
an = 0
converges. This is called the alternating series test.