Module 9 :  Infinite Series, Tests of Convergence,  Absolute and Conditional Convergence, Taylor and Maclaurin Series
Lecture 27 :  Series of functions [Section 27.1]
 

This is a power series centered at . For its convergence, let us apply the limit ratio test. Since



the series is convergent absolutely for ,and is divergent for other values of

For , the series is ,

which is a divergent series. Also for , it is the alternating harmonic series. Thus, the given power series is convergent with domain of convergence being the interval

The domain of convergence if a power series is given by the following theorem.

27.1.3 Theorem :
 

For a power series

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