Question

The Sum of the rst n terms of an A.P. is given by:

Sn = n

2

[2a + (n − 1)d]. The following are the steps involved in making d as the

subject of the formula. Arrange them in sequential order.

(A) 2a + (n − 1)d = 2S

n

n

(B) d = 2

n 1

S

n

a n

− −









(C) Sn = n

2

[2a + (n − 1)d] ⇒ 2Sn = n[2a + (n − 1)d]

(D) (n − 1)d = 2S

n

n − 2a Its class 7 ​

Answer 1

boht hard to understand.

plzz post it again properly.