Quadratic Equations-Sample Papers

1.   If T_n = 3 + 4n then find the A.P. and hence find the sum of its first 15 terms.

2.   Which term of the A.P.:

       3, 15, 27, 39, .... will be 120 more than its 53rd term?

3.   Find the 31st term of an A.P. whose 10th term is 31 and the 15th term is 66.

4.   If the 8th term of an A.P. is 37 and the 15th term is 15 more than the 12th term, find the A.P. Hence find the sum of the first 15 terms of the A.P.

5.   The 5th and 15th terms of an A.P. are 13 and �17 respectively. Find the sum of first 21 terms of the A.P.

6.   In an A.P. the sum of its first ten terms is �150 and the sum of its next erm is �550. Find the A.P.

7.   The sum of n terms of an A.P. is 3n² + 5n. Find the A.P. Hence, find its 16th term.

8.   In an A.P., the first term is 8, nth term is 33 and sum of first n terms is 123. Find n and d, the common difference.