Which term of the AP: 121, 117, 113,……… is the first negative term?
[Hint:Find n for `a_(n) lt 0`]

Which term of the AP 121, 117,113,......is its first negative term ?

Which term of the AP , 45,41,37,33 it its first negative term ?

Which term of the AP 75, 72, 69, ... is its first negative term ? If it is the nth term, find S_n .

Find the rth term of an AP sum of whose first n terms is 2n+ 3n^(2)

Fill in the blanks in the following table, given that a is the first term, d the common difference and a_(n) the nth term of the A.P.

The sum of the first 7 terms of an AP is 63 and the sum of its next 7 terms is 161. Find the 28th term of this AP.

Write first four terms of the AP. When the first term a and the common difference d are given as follows : a= -2 , d = 0

The first term of an AP is 5, the last term is 45 and the sum is 400. Find the number of terms and the common difference.

If the sum of the first n terms of an AP is 4n - n^2 , what is the first term (that is S_1 ) ? What is the sum of first two terms ? What is the second term ? Similarly . Find the 3rd, the 10th and the nth terms .

If the sum of first n terms of an AP is 1/2 (3n^(2) + 7n) , then find its nth term. Hence write its 20th term.