Published by:
CGP EDU Academic Team
Published on: August 12, 2026
In a triangle ABC, if cos A + 2cos B + cos C = 2, then a, b, c
are in -
Text Solution
Verified by ExpertsThe correct answer is:
A
cos A + 2cos B + cos C = 2
⇒ cos A + cos C = 4 sin 2 
⇒ 2cos 
cos 
= 4 sin 2 
⇒ cos 
= 2cos 
⇒ cot A/2 cot C/2 = 3
× 
= 3
⇒ s = 3(s – b) ⇒ 2s = 3b ⇒ a + c = 2b
⇒ a, b, c are in A.P.
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