When the series have been known to be convergent or divergent,and we want to determine whether the new series converges or diverges.At this situation,we can use the comparison tests to compare a given series with a series that is known.For example:When we see the new series When the series have been known to be convergent or divergent, and we want to determine whether the new series converges or diverges. At this situation, we can use the comparison tests to compare a given series with a series that is known.For example: When we see the new series