Question

formula of s.n..Ap .........​

Answer 1

Answer:

sn=n/2(2a+(n-1)d)

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Answer 2

Answer:

The general form of an Arithmetic Progression is a, a + d, a + 2d, a + 3d and so on. Thus nth term of an AP series is Tn = a + (n - 1) d, where Tn = nth term and a = first term. Here d = common difference = Tn - Tn-1. The sum of n terms is also equal to the formula where l is the last term.

formula of an is =Sn =a(1 − rn) 1 − r .