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In DeltaABC if r(1)=R then...

In `DeltaABC` if `r_(1)=R` then

A

`CosA+CosB+CosC=2`

B

`CosB+CosC=CosA`

C

`CosA+CosB=CosC`

D

`CosB+CosC+CosA`

Text Solution

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The correct Answer is:
D
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AAKASH SERIES-REVISION EXERCISE-PROPERTIES OF TRIANGLES
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