Find the nth term of the AP: 11, 8, 5, 2 ... Write the recursive rule for this AP. Class 9

Find the n^th term of the AP: 11, 8, 5, 2 ... Write the recursive rule for this AP. Class 9

Question 1.

Find the n^th term of the AP: 11, 8, 5, 2 ... Write the recursive rule for this AP. Class 9

Solution:

The given AP is 11, 8, 5, 2...

a = 11, d = 8 - 11 =-3

∴ t_n = a + (n - 1) d

∴ t_n = 11 + (n - 1)(-3)

∴ t_n> = 11 - 3(n - 1)

∴ t_n = 11 - 3n + 3

∴ t_n = 14 - 3 n

∴ n^th term of the AP is t_n = 14 - 3n

ii. Recursive rule for the given AP is

t₁ = a, t_n-1 + d for n ≥ 2

∴ t₁ = 11, t_n = t_n-1 - 3 or n ≥ 2