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If S1, S2, ,Sn are the sum of n term of...

If `S_1, S_2, ,S_n` are the sum of `n` term of `n` G.P., whose first term is 1 in each and common ratios are `1,2,3, ... ,n` respectively, then prove that `S_1+S_2+2S_3+3S_4+(n-1)S_n=1^n+2^n+3^n++n^n`.

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`S_1, S_2, ,S_n` are the sum of `n` term of `n` G.P., whose first term is 1 in each and common ratios are `1,2,3, ... ,n`

`:. S_1 = 1+1+1+..... n terms = n .....` (i)
...
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