Question

3.The sum of the first n even natural numbers. ​

Answer 1

Answer:

The even natural numbers are:

2,4,6,8,.............

Here, a= 2 and. d= 4-2 = 2

Now ,

Sn = n/2 [2a +(n-1)d ] ....... ( By formula)

Sn = n/2 [ 2(2) + (n-1) 2) ]

= n/2 ×2 (2+ n-1)

= n ( 1+n)