trigonometry

Related Questions

• $\cos \alpha .\sin (\beta -\gamma )+\cos \beta .\sin (\gamma -\alpha )+\cos \gamma .\sin (\alpha -\beta )=$

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• If $\cos \theta =\frac{8}{17}$ and $\theta $ lies in the 1st quadrant, then the value of $\cos (30{}^\circ +\theta )+\cos (45{}^\circ -\theta )+\cos (120{}^\circ -\theta )$ is

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• $\frac{\sin \theta }{1-\cot \theta }+\frac{\cos \theta }{1-\tan \theta }=$

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

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• $1-2{{\sin }^{2}}\left( \frac{\pi }{4}+\theta \right)=$

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