Published by:
CGP EDU Academic Team
Published on: August 12, 2026
Let < a n > be a G.P. such that 
and a 2 + a 5 = 216. Then a 1 is equal to
A
12 or 
B
10
C
7 or 
D
None of these
Text Solution
Verified by ExpertsThe correct answer is:
A
Let the G.P. be a, ar, ar 2 , ……………….
= 
r 2 = 4 ; r = 2, – 2
case-I : If r = 2
a 2 + a 5 = 216
ar + ar 4 = 216
a 1 = 12, r = 2
case-II : r = – 2
a 2 + a 5 = 216
ar + ar 4 = 216
a = 
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