Question

Find the sum of odd integers from 1 to 2001.

Answer 1

The odd integers from 1 to 2001 are 1, 3, 5 …1999, 2001.
This sequence forms an A.P.
Here, first term, a = 1
Common difference, d = 2

Thus, the sum of odd numbers from 1 to 2001 is 1002001.