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If angles A,B,C are in A.P . , then 2c...

If angles A,B,C are in A.P . , then ` 2cos (( A-C)/( 2))= `

A

`( a+c) /(sqrt(a^(2) - ac+ c^(2)) `

B

` ( a+c) /( sqrt(a^(2) + ac+ c^(2))`

C

` ( a+c) /( sqrt( a^(2) - ac-c^(2))`

D

` ( a+ c)/( sqrt( a^(2) + 2ac -c^(2))`

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A
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AAKASH SERIES-PROPERTIES OF TRIANGLES-EXERCISE - II
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