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Question
Find the sum of the following geometric series:
x3, x5, x7, ... to n terms
Solution
The given G.P. is x3, x5, x7 ........
Here, a = x3 and r = x2
`"S"_"n" = (a(1 - r^n))/(1 - r)`
= `(x^3[1 - (x^2)^n])/(1 - x^2)`
= `(x^3(1 - x^(2n)))/(1 - x^2)`
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