Question

write. the. farmula. to. find. sum. of. first. n. terms. of. ap​

Answer 1

Step-by-step explanation:

the sum of first n terms of an Arithmetic Progression is S = n2[2a + (n - 1)d]. In the formula there are four quantities. They are S, a, n and d. If any three quantities are known, the fourth quantity can be determined.

Suppose when two quantities are given then, the remaining two quantities are provided by some other relation.

2. When the sum Sn of n terms of an Arithmetic Progression is given, then the nth term a_n of the Arithmetic Progression cann be determined by the formula an = Sn - Sn−1.