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If 450^(@) lt A lt 540^(@), sin A = 3//5...

If `450^(@) lt A lt 540^(@), sin A = 3//5 `, then ` cos A//2=`

A

`3//sqrt(10)`

B

`-3//sqrt(10)`

C

`1/sqrt(10)`

D

`-1//sqrt(10)`

Text Solution

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The correct Answer is:
D
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DIPTI PUBLICATION ( AP EAMET)-TRIGONOMETRIC RATIOS AND IDENTITIES -EXERCISE 2 ( SPEICAL TYPE QUESTIONS ) SET -4
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