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In a triangle ABC, let 2a^2+4b^2+ c^2= 2...

In a triangle ABC, let `2a^2+4b^2+ c^2= 2a(2b + c)` , then which of the following holds good?

A

` cos B =(-7)/(8)`

B

`sin (A-C)=0`

C

`(r )/(r_(1) `=`1/5`

D

`sin A : sin B :sin C=1:2:1`

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The correct Answer is:
A, B, C
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ARIHANT MATHS-PROPERTIES AND SOLUTION OF TRIANGLES -Exercise (Questions Asked In Previous 13 Years Exam)
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