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cos 690^(@) * sin 840^(@) + cos 420^(@) ...

`cos 690^(@) * sin 840^(@) + cos 420^(@) * sin 1050^(@)=`

A

0

B

`1//2`

C

`1//5`

D

1

Text Solution

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The correct Answer is:
B
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DIPTI PUBLICATION ( AP EAMET)-TRIGONOMETRIC RATIOS AND IDENTITIES -EXERCISE 1 A ( TRIGONOMETRIC FUNCTIONS)
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