trigonometry

Related Questions

• If the line segment joining the points $A(a,\,b)$ and $B(c,\,d)$ subtends an angle $\theta $ at the origin, then $\cos \theta $ is equal to

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• The value of $\cos y\cos \left( \frac{\pi }{2}-x \right)-\cos \left( \frac{\pi }{2}-y \right)\cos x$ $+\sin y\cos \left( \frac{\pi }{2}-x \right)+\cos x\sin \left( \frac{\pi }{2}-y \right)$ is zero, if

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• The value of $\sin \frac{\pi }{16}\sin \frac{3\pi }{16}\sin \frac{5\pi }{16}\sin \frac{7\pi }{16}$is

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• If $\alpha ,\beta ,\gamma $ are angles of a triangle, then ${{\sin }^{2}}\alpha +{{\sin }^{2}}\beta +{{\sin }^{2}}\gamma -2\cos \alpha \cos \beta \cos \gamma $ is

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• If ABCD is a cyclic quadrilateral, then the value of $\cos A-\cos B+\cos C-\cos D=$

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