Solution:
Given AP: 11, 8, 5, 2,…
First term, a = a1 = 11
Common difference, d = a2− a1 = 8−11 = −3
Let −150 be the nth term of the AP.
We know that,
an = a + (n −1) d
-150 = 11+ (n – 1)(-3)
-150 = 11 – 3n + 3
-164 = -3n
n = 164/3
Clearly, n is not an integer but a fraction.
Therefore, –150 is not a term of the given AP.