Find the 20^th and n^th terms of the G.P 5/2, 5/4, 5/8 ....

Solution:

The given G.P. is

5/2, 5/4, 5/8 ....

Hence, a = 5/2 and r = (5/4)/(5/2)

= 1/2

Therefore,

a₂₀ = ar^{20 - 1} = 5/2 (1/2)¹⁹ = 5/[(2) (2)¹⁹]

= 5/(2)²⁰

a_n = ar^{n - 1} = 5/2 (1/2)^{n - 1} = 5/[(2) (2)^{n - 1}]

= 5/(2)ⁿ

NCERT Solutions Class 11 Maths Chapter 9 Exercise 9.3 Question 1

Find the 20^th and n^th terms of the G.P 5/2, 5/4, 5/8 ....

Summary:

Therefore, the 20th and the nth terms of the G.P are 5/(2)²⁰ and 5/(2)ⁿ