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sin 21^(@) cos 9^(@) - cos 84^(@) cos 6^...

`sin 21^(@) cos 9^(@) - cos 84^(@) cos 6^(@)=`

A

`1//2`

B

`-1//2`

C

`1//4`

D

`-1//4 `

Text Solution

Verified by Experts

The correct Answer is:
C
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DIPTI PUBLICATION ( AP EAMET)-TRIGONOMETRIC RATIOS AND IDENTITIES -EXERCISE 1 D ( TRANSFORMATIONS )
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