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cos A/2=sqrt((b+c)/(2c)) then the correc...

`cos `A/2`=sqrt((b+c)/(2c))` then the correct option is

A

a)`a^2+b^2=c^2`

B

b)`c^2+a^2=b^2`

C

c)`b^2+c^2=a^2`

D

d)none of these

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The correct Answer is:
A
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PATHFINDER-TRIGONOMETRIC FUNCTIONS-QUESTION BANK
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