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Question
The nth term of an A.P., the sum of whose n terms is Sn, is
Options
Sn + Sn−1
Sn − Sn−1
Sn + Sn+1
Sn − Sn+1
Solution
A.P. we use following formula,
`a_n = S_n - S_(n - 1)`
So, the nth term of the A.P. is given by `a_n = S_n - S_(n - 1)`.
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