Question -
Answer -
Given an AP of first nodd natural numbers whose first term a is 1, and common difference d is 3
The sequence is 1, 3,5, 7……n
a = 1, d = 3-1 = 2, n= n
By using the formula,
S = n/2 [2a + (n-1)d]
= n/2 [2(1) + (n-1)2]
= n/2 [2 + 2n – 2]
= n/2 [2n]
= n2
∴ The sum of the firstn odd natural numbers is n2.