Question

If the 11th term of an A.P is -21 and the sum of first 7 term -49 ,find the A.P​

Answer 1

Answer:

First term, a=−17. Common difference, d = a2 −a1 = −12−(−17) = 5. We know that, an =a+(n−1)d a11 = −17+(11−1)(5)