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Let a1,a2 ,a3 ...... be an A.P. Prove th...

Let `a_1,a_2 ,a_3` ...... be an A.P. Prove that `sum_(n=1)^(2m)(-1)^(n-1)a_n^2=m/(2m-1)(a_1^2-a_(2m)^2)`.

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PATHFINDER-PROGRESSION AND SERIES -QUESTION BANK
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  13. Find the sum to n terms of the series 1/(1 + 1^2 + 1^4) + 2/(1 + 2^2...

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  14. Evaluate , S =sum(n = 0)^infty 2^n/(a^(2^n) + 1) (where a gt 1)

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