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Prove that (1+cos(A-B)cosC)/(1+cos(A-C)c...

Prove that `(1+cos(A-B)cosC)/(1+cos(A-C)cosB)=(a^(2)+b^(2))/(a^(2)+c^(2))`

A

` ( a^(2)+b^(2))/( a^(2) + c^(2))`

B

` ( a^(2)-b^(2))/( a^(2) - c^(2))`

C

` 2( ( a^(2)+b^(2))/( a^(2) + c^(2)))`

D

` 3( ( a^(2)+b^(2))/( a^(2) + c^(2)))`

Text Solution

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The correct Answer is:
A
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AAKASH SERIES-PROPERTIES OF TRIANGLES-PRACTICE EXERCISE
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