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# The sum of n terms of an AP is. Find the common difference.

Answer :

Given: the sum of n terms of an AP is.

To find: common difference.

put n = 1 we get

First term =

Put n = 2 we get

First term + second term = 2 × a + 2 × b

Second term =

Therefore common difference will be

Second term – first term

Common difference = 2a

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