Find the sum Sn of the first terms of : 1+3+5+...+(2n-1)

Question

Sum of n terms of an arithmetic sequence formula is Sn=n(a1+a2)

Answer 1

Given arthimetic series 1+3+5+....+(2n-1)

First term a1 = 1

Here we find the sum of first two terms.

Sum of terms Sn = n/2(a+l)

a = first term and l is last term.

Sn = 2/2(1+3) = 4