Published by:
CGP EDU Academic Team
Published on: August 12, 2026
If in a triangle ABC, cos A cos B + sin A sin B sin C = 1, then the triangle is
Text Solution
Verified by ExpertsThe correct answer is:
A
sin C = 
≤ 1 ⇒ cos (A – B) ≥ 1 ⇒ cos (A – B) = 1
⇒ A – B = 0 ⇒ A = B ∴ sin C = 
= 1 ⇒ C = 90º
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