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Sapphy Sapphy is offline
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Default Summation Operator

Hi,
I'm trying to work out a way of getting Excel 2003 to answer

y=2i+1 when i=1 initially with a final value of 10.
y=(2x1+1)+(2x2+1)+...+(2x10+1)

I could type it by hand however my next question requires the upper limit n
to be infinity for the eqn

y=1/i(i-1) when i=1 initially and the final value for i=infinity
y=(1/(1(1+1))+(1/2(2+1)+...(1/infinity(infinity+1)

and I eed to find the approximate answer for y when the addition of the
successive terms causes a lass than 0.0001% change in y, as well as the last
value for i when the program stops.

Am utterly stumped! Please help,

Thank you.