Hi all. I have been asked to sum this series:
and also asked what the sum is to infinity when |x|< 1
I have all of the formulae (dodgy spelling ) for summing a series and sum to infinity but this one has me stumped; mainly because at the back of the text book the given anser is:
I just don't know how to get this answer. It's caused a bit of a mental block for me and his becoming quite annoying! Any help on working through to get this answer would be really helpful and much appreciated. Thanks in advance!