Question

What is the formula to find sum of an AP?

Answer 1

Hey there ,

The formula to find some of an AP are :-

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

If last term is given then use :-

Sn = n/2 [a + l]

Here ,

Sn = Sum of 'n' terms.
n = total number of terms.
l = last term.
a = first term.
d = common difference.

Hope it helps :)

Answer 2

Answer:

Step-by-step explanation:

Sum of an AP : Sn=n/2[2a+(n-1)d]

Or if you have An(last term)then: Sn=n/2[a+An]