This is arithmetic progression based question from Chapter name- Arithmetic Progression
Chapter number- 9
Exercise – 9.4
In this question we have been given the arithmetic progression. Also we have to find Which term of the AP 84, 80, 76, … is 0
CBSE DHANPAT RAI PUBLICATIONS
Understanding CBSE Mathematics
Class :- 10th
Question no 2(ii)
Given that,
A. P is 84, 80, 76, …………
First term (a) = 84
nth term is 0
Common difference (d) = a2 – a
d = 80 – 84 = – 4
As we know that, to find nth term in an A.P = a + (n – 1)d
0 = 84 + (n – 1) – 4
84 = +4(n – 1)
n – 1 = 84/4 = 21
n = 21 + 1 = 22
Hence 22nd term in the A.P is 0.