trigonometry

Related Questions

• The expression ${{\cos }^{2}}(A-B)+{{\cos }^{2}}B-2\cos (A-B)\cos A\cos B$ is

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• If the angles of a triangle $ABC$ be in A.P., then

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• If $\sin \theta +\sin \varphi =a$and $\cos \theta +\cos \varphi =b,$then $\tan \frac{\theta -\varphi }{2}$is equal to

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• If $\sin \theta =\frac{24}{25}$and $\theta $ lies in the second quadrant, then $\sec \theta +\tan \theta =$

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• If $\tan (\pi \cos \theta )=\cot (\pi \sin \theta ),$then the value of $\cos \left( \theta -\frac{\pi }{4} \right)$=

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