If the sum of n terms of a sequence is quadratic expression, then it always represents an AP.

Find the sum of 7 terms of the sequence 2, 6, 18,……

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 n terms of an AP is cn^(2) , then the sum of squares of these n terms is

Find the sum to n terms of the sequence, 8, 88, 888, 8888… .

If the sum of p terms of an A.P. is q and the sum of q terms is p, then the sum of p+q terms will be

If the sum of m terms of an A.P. is equal to the sum of either the next n terms or the next p terms, then prove that (m+n)(1/m-1/p)=(m+p)(1/m-1/n)dot

If the sum of p terms of an AP is q and the sum of q terms is p, then show that the sum of p+q terms is -(p+ q) . Alos, find the sum of first p-q terms (where, p gt q )

If the sum of the first ten terms of an A.P is four times the sum of its first five terms, the ratio of the first term to the common difference is:

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