trigonometry

Related Questions

• If $5\cos 2\theta +2{{\cos }^{2}}\frac{\theta }{2}+1=0,-\pi <\theta <\pi $, then $\theta =$

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• The expression $2\cos \frac{\pi }{13}.\cos \frac{9\pi }{13}+\cos \frac{3\pi }{13}+\cos \frac{5\pi }{13}$ is equal to

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• If $x=a{{\cos }^{3}}\theta ,y=b{{\sin }^{3}}\theta ,$then

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• If $\cos \theta +\sec \theta =\frac{5}{2}$, then the general value of $\theta $is

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• In $\Delta ABC,$ if $a=16,b=24$ and $c=20,$ then $\cos \frac{B}{2}=$

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