Question #2af10

1 Answer
May 23, 2017

Common ratio is # 1 1/2#

Explanation:

#3# rd term of A.P is # a+(3-1)b = a+2b#

#5# th term of A.P is # a+(5-1)b = a+4b#

#8# th term of A.P is # a+(8-1)b = a+7b#

#3# consecutive terms of G.P are #a+2b,a+4b,a+7b #.
in G.P
# (a+4b)/(a+2b)=(a+7b)/(a+4b) or (a+4b)^2=(a+2b)(a+7b)# or

# cancela^2+8ab+16b^2= cancela^2+9ab+14b^2# or
# 2b^2= ab or a= 2b#

#3# consecutive terms of G.P are #4b,6b,9b #

Common ratio is # r= (6b)/(4b)=3/2 or (9b)/(6b)= 3/2# [Ans]