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If `S_n` denotes the sum to n terms of the series `(1 le n le 9)` 1 + 22 + 333 + .... + 999999999 then for `n ge 2`

A

`S_n - s_(n - 1) = 1/9 (10^n - n^2 + n)`

B

`S_n = 1/9 (10^n - n^2 + 2n - 2)`

C

`9(S_n - S_(n - 1)) = n (10^n - 1)`

D

`S_3 = 356`

Text Solution

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The correct Answer is:
C, D
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