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If sin theta =-4/5 and theta lies in...

If `sin theta =-4/5` and `theta` lies in third quadrant, then the value of `cos (theta/2)` is

A

`(1)/(sqrt5)`

B

`-(1)/(sqrt5)`

C

`sqrt((2)/(5))`

D

`-sqrt((2)/(5))`

Text Solution

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The correct Answer is:
B
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