Ratio Test for Infinite Series Explained | Calculus 2

We introduce the ratio test for showing an infinite series is absolutely convergent. Note that absolute convergence is stronger than normal convergence, so when we use the ratio test to show that a series is absolutely convergent, we also establish it is convergent in the usual sense. The ratio test requires us to evaluate the limit of the magnitude of the ratio of consecutive terms of the series. If this limit is less than 1 than the series is absolutely convergent, if the limit is greater than 1 then the series is divergent, if the limit is equal to 1 then the test is inconclusive. #apcalculusbc #calculus2

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0:00 Intro
0:21 Definitions
1:18 Ratio Test
3:01 Example 1 (-1)^n*n^2/2^n
6:10 Example 2 n^n/n!
8:49 Example 3 1/n^2
9:59 When to use Ratio Test
11:17 Conclusion