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If in a triangle ABC, B =(2pi)/3, then ...

If in a triangle ABC, B =`(2pi)/3,` then cosA +cosC lies in

A

`[-sqrt3,sqrt3]`

B

`(-sqrt3,sqrt3]`

C

`(3/2,sqrt3)`

D

`[3/2,sqrt3]`

Text Solution

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The correct Answer is:
C
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