Advertisement
Advertisement
Last updated at May 29, 2018 by Teachoo
Transcript
Ex9.3, 11 Introduction (2 + 3k) At k = 1, 2 + 31 At k = 2, 2 + 32 .. โฆ โฆ. At k = 11, 2 + 311 Ex9.3, 11 We calculate (31 + 32 + 33 + โฆ + 311) separately In 31 + 32 + 33 + โฆ + 311 32/31 = 3 & 33/32 = 3 Thus, (๐๐๐๐๐๐ ๐ก๐๐๐)/(๐น๐๐๐ ๐ก ๐ก๐๐๐) = (๐โ๐๐๐ ๐ก๐๐๐)/(๐๐๐๐๐๐ ๐ก๐๐๐) i.e. common ratio is same Thus, it is a G.P. First term = a = 3 Common ratio = 3^2/3^1 = 3 Since, r > 1 โด Sn = (๐(๐^๐ โ 1))/(๐ โ 1) where Sn = sum of n terms of GP n is the number of terms a is the first term & r is the common ratio โด Sn = (๐(๐^๐ โ 1))/(๐ โ 1) Putting values a = 3 , r = 3, n = 11 S11 = (3[311โ1])/(3 โ 1) S11 =(3[311โ1])/2 Hence 31 + 32 + โฆ + 311 = (3[311โ1])/2 From (1) Putting 31 + 32 + โฆ + 311 = (3[311โ1])/2 = 22 + (3(311 โ 1))/2 =22 + 3/2(311 โ1) Therefore,
Ex 9.3
Ex 9.3, 2
Ex 9.3, 3 Important
Ex 9.3, 4
Ex 9.3, 5 (a)
Ex 9.3, 5 (b) Important
Ex 9.3, 5 (c)
Ex 9.3, 6
Ex 9.3, 7 Important
Ex 9.3, 8
Ex 9.3, 9 Important
Ex 9.3, 10
Ex 9.3, 11 Important You are here
Ex 9.3, 12
Ex 9.3, 13
Ex 9.3, 14 Important
Ex 9.3, 15
Ex 9.3, 16 Important
Ex 9.3, 17 Important
Ex 9.3, 18 Important
Ex 9.3, 19
Ex 9.3, 20
Ex 9.3, 21
Ex 9.3, 22 Important
Ex 9.3, 23 Important
Ex 9.3, 24
Ex 9.3, 25
Ex 9.3, 26 Important
Ex 9.3, 27 Important
Ex 9.3, 28
Ex 9.3, 29 Important
Ex 9.3, 30 Important
Ex 9.3, 31
Ex 9.3, 32 Important
Ex 9.3
About the Author