Math, asked by vanshika85, 1 year ago

if the sum of first seven terms of an AP is 49 and the sum of its first seventeen terms is 289 find the sum of first n terms of the AP

Answers

Answered by Anonymous
1
than backput d in 1 st eqn to find a and then write the summision of ap formula
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Anonymous: which is n/2(2a+{n-1}d)
xyz89: formula to find out sn term
xyz89: sn = n/2 (2a + (n-1 )d
xyz89: d)
Answered by xyz89
3
this is the solution or value of sn. is n^2

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