Question

The sum of the first 26 terms of an AP 1,3,5,7, ... is -​

Answer 1

Answer:

answer : 702

Step-by-step explanation:

here , a = 1 , d = 3-1=2

Sn = n/2(2a + (n-1) × d

= 26/2(2×1 + (26-1)×2

= 13 ( 2 + 25)×2

= 13 ×27 × 2

= 26 × 27

= 702