trigonometry

Related Questions

• If $x{{\sin }^{3}}\alpha +y{{\cos }^{3}}\alpha =\sin \alpha \cos \alpha $ and $x\sin \alpha -y\cos \alpha =0,$ then ${{x}^{2}}+{{y}^{2}}=$

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• If $\tan \theta +\tan 2\theta +\tan 3\theta =\tan \theta \tan 2\theta \tan 3\theta $, then the general value of $\theta $ is

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• If $\cot \theta +\tan \theta =2\text{cosec}\theta $, the general value of $\theta $ is

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• If $\sin 2\theta +\sin 2\varphi =1/2$ and $\cos 2\theta +\cos 2\varphi =3/2$, then ${{\cos }^{2}}(\theta -\varphi )=$

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• If $\sin A+\sin B=C,\cos A+\cos B=D,$then the value of $\sin (A+B)=$

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