Ex 8.2

Ex 8.2, 1
You are here

Ex 8.2, 2

Ex 8.2, 3 Important

Ex 8.2, 4

Ex 8.2, 5 (a)

Ex 8.2, 5 (b) Important

Ex 8.2, 5 (c)

Ex 8.2, 6

Ex 8.2, 7 Important

Ex 8.2, 8

Ex 8.2, 9 Important

Ex 8.2, 10

Ex 8.2, 11 Important

Ex 8.2, 12

Ex 8.2, 13

Ex 8.2, 14 Important

Ex 8.2, 15

Ex 8.2, 16 Important

Ex 8.2, 17 Important

Ex 8.2, 18 Important

Ex 8.2, 19

Ex 8.2, 20

Ex 8.2, 21

Ex 8.2, 22 Important

Ex 8.2, 23 Important

Ex 8.2, 24

Ex 8.2, 25

Ex 8.2, 26 Important

Ex 8.2, 27 Important

Ex 8.2, 28

Ex 8.2, 29 Important

Ex 8.2, 30 Important

Ex 8.2, 31

Ex 8.2, 32 Important

Chapter 8 Class 11 Sequences and Series

Serial order wise

Last updated at April 16, 2024 by Teachoo

Ex 8.2, 1 Find the 20th and nth terms of the G.P. 5/2, 5/4, 5/8,…. G.P. is 5/2, 5/4, 5/8,…. We know that an = arn – 1 where an = nth term of GP n is the number of terms a is the first term r is the common ratio Here, First term a = 5/2 Common ratio r = (5/4)/(5/2) = 5/4 × 2/5 = 1/2 We need to find nth term, nth term of GP = an = arn-1 Putting a = 5/2 , d = 1/2 = 5/2 (1/2)^(𝑛−1) = 5/2 (1/2^(𝑛−1) ) = (5/(〖2 (2〗^(𝑛−1)))) = 5/(2)"n − 1 + 1" = 5/2^𝑛 Hence, the nth term of GP is 5/2^𝑛 For 20th term of GP Putting n = 20 in an a20 = 5/2^20 Thus, 20th term of GP is 5/2^20