Let be the sum of the first terms of an arithmetic progression (AP) and its th term

MATHEMATICS · Subjective · CBSE · Mathematics · Arithmetic Progressions · Arithmetic Progressions

Problem

Let

S_n

be the sum of the first

n

terms of an arithmetic progression (AP) and

a_n

its

n

th term. Show that

a_n = S_n - S_{n-1}