191. If the sum of first n terms of an A.P. is Zero, then the sum of next m terms, where a is the first term of the A.P. is

If the sum of first p terms of an A.P is equal to the sum of the first q terms , then find the first (p+q) terms .

If the sum of first 7 terms of an A.P. is 49 and that of its 17 terms is 289, find the sum of first n terms of the A.P.

If the sum of first p terms of an A.P. is equal to the sum of the first q terms, then find the sum of the first (p+q) terms.

If the sum of first p terms of an A.P. is equal to the sum of the first q terms, then find the sum of the first (p+q) terms.

If sum of first 20 terms of an A.P. is equal to sum of first 30 terms of the A.P. then sum of the first 50 terms of the A.P. is

If the sum of first 7 terms of an A.P is 49 and that of its first 17 terms is 289, find the sum of first n terms of the A.P

If the sum of first 7 terms of an A.P. is 49 and that of 17 terms is 289, find the sum of first n terms.

If the sum of first 7 terms of an A.P is 49 and that of 17 terms is 289, find the sum of first n terms.

The n^(th) term of an A.P is p and the sum of the first n terms is s. The first term is