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In any triangle ABC, if cosA cos B + sin...

In any triangle ABC, if cosA cos B + sin A sin B sinC =1 then prove that the triangle in an isosceles right angled.

A

isosceles

B

right angled

C

isosceles right angles

D

equilateral

Text Solution

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The correct Answer is:
C
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OBJECTIVE RD SHARMA-PROPERTIES OF TRIANGLES AND CIRCLES CONNECTED WITH THEM-Exercise
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