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Find the angle theta whose cosine is equ...

Find the angle `theta` whose cosine is equal to its tangent.

A

`cos theta=2cos18^(@)`

B

`cos theta=2sin18^(@)`

C

`sintheta=2 sin18^(@)`

D

`sintheta=2cos18^(@)`

Text Solution

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The correct Answer is:
C
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OBJECTIVE RD SHARMA ENGLISH-TRIGONOMETRIC RATIOS AND IDENTITIES-Exercise
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