Here's the problem:

1 - 2 + 2^2 - 2^3 + ... + [(-1)^n][2^n]

i'm trying to get the summation with [r^(n+1) - 1] / [r - 1]

i can't figure out what r is

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- Nov 25th 2006, 05:36 AMergoSumgeometric sum problem
Here's the problem:

1 - 2 + 2^2 - 2^3 + ... + [(-1)^n][2^n]

i'm trying to get the summation with [r^(n+1) - 1] / [r - 1]

i can't figure out what r is - Nov 25th 2006, 11:07 AMtopsquark