Question

derive the formula for the sum of first n terms of AP,whose first term is a and the common difference is d.
PLEASE EXPLAIN ,DON'T WRITE THE ANSWER ONLY.
AND EXPLAIN IN A EASY WAY ,DON'T IN A DIFFICULT MANNER THEN I WILL GIVE YOU BRAINLIEST ANSWER.​

Answer 1

Answer:

here is your answer....

Step-by-step explanation:

Suppose, a1, a2, a3, ……….. be an Arithmetic Progression whose first term is a and common difference is d. Therefore, S = n2[2a + (n - 1)d] = n2[a {a + (n - 1)d}] = n2(a+l)

Answer 2

sn = n/2 (2a +( n - 1 ) d )

sn = sum of the n terms

n = nth term

a = frist term

d = common difference