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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

Verified by Experts

The correct Answer is:
C
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OBJECTIVE RD SHARMA-TRIGONOMETRIC RATIOS AND IDENTITIES-Exercise
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  2. If 2cos""(A)/(2)=sqrt(1+sinA)+sqrt(1-sinA), thenA/2 iles between,

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

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  5. Find the value of : cos(pi/15)cos((2pi)/15)cos((3pi)/15)cos((4pi)/15)c...

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  8. If abs(cos theta{sin theta+sqrt(sin^2theta+sin^2alpha)})lek, then the ...

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  12. If sinA+sinB=a and cosA+cosB=b,then cos(A+B)

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  13. If an angle theta is divided into two parts A and B such that A-B=x an...

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  14. The value of the expression 3(sin theta- cos theta)^4 + 6(sin theta ...

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  15. If tan((theta)/(2))=5/2and tan((phi)/(2))=3/4, the value of cos(theta+...

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  16. If alpha,beta, gamma in(0,(pi)/(2)), then prove that (Sin(alpha+beta+g...

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