If the 2nd, 5th and 9th terms of a non-constant A.P. are in G.P., then the common ratio of this G.P. is :
As we learnt in
Common ratio of a GP (r) -
The ratio of two consecutive terms of a GP
- wherein
eg: in 2, 4, 8, 16, - - - - - - -
r = 2
and in 100, 10, 1, 1/10 - - - - - - -
r = 1/10
are in G.P where are Terms of an A.P
Let first term is a and common difference is d, and common ratio be r then
A = a+d
B = a+4d
C= a+8d
from (i) and (ii)
2a=16d
a=8d
Option 1)
Incorrect option
Option 2)
Correct option
Option 3)
Incorrect option
Option 4)
Incorrect option
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