If the sum of n terms of an AP is 2n + 5 then prove that aN =4n+3

1.	If the sum of n terms of an AP is 2n + 5 then prove that aN =4n+3
Answer» Since,. Sn=2n+5. Therefore,. Sn-1=2(n-1)+5 Or,. =2n+3. We Know that,. An=Sn-Sn-1. Or,. =2n-1-(2n+3). Or,. = -4 Since, value of n donot exist Therefore this donot form any A.P. Please check your question Sn must be 2n²+5

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