How to derieve the formula for sum of series

I'm able to analyze and solve the equation till i get some specific series like T(n)=1+2+3+...n and other type of series but i'm unable to know how to determine the formula for the series derieved like sum of 1st n natural numbers is said to be n(n-1)/2 so how to derieve formula's for any series

1Comment
Sashi Kumar Singh @sashisingh
4 Jul 2017 04:24 am

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