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If sintheta=(-4)/(5) and theta lies in t...

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

A

`1//5`

B

`- 1// sqrt( 10)`

C

`-1 // sqrt( 5)`

D

`1// sqrt( 10)`

Text Solution

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The correct Answer is:
C
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ML KHANNA-TRIGONOMETRY RATIOS AND IDENTITIES-MISCELLANEOUS EXERCISE (SELF ASSESSMENT TEST)
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