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closed form simplification
Posted:
Nov 18, 1999 12:34 AM


I'm not seeing this and it looks so obvious ...
here is the series I'm looking at:
sum {from i=1 to r} ip^i = p sum(i=1 to r)ip^(i1)
now this RHS looks like p multiplied by the derivative of the LHS. Can I use the identity 1+p+...+p^s = (1p^(s+1))/(1p) ? ...just differentiate it once? If not what does this sum simplify to?
Thanks for the help, Kathleen



