trigonometry

Related Questions

• 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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• In a $\Delta ABC,$ $2a\sin \,\,\left( \frac{A-B+C}{2} \right)$ is equal to

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• In triangle ABC, the value of $\sin 2A+\sin 2B+\sin 2C$ is equal to

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• .Given that $\cos \left( \frac{\alpha -\beta }{2} \right)=2\cos \left( \frac{\alpha +B}{2} \right)$, then $\tan \frac{\alpha }{2}\tan \frac{\beta }{2}$is equal to

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• If $2{{\cos }^{2}}x+3\sin x-3=0,\,\,0\le x\le {{180}^{o}}$, then $x =$

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