trigonometry

Related Questions

• The value of $\cos (270{}^\circ +\theta )\,\cos (90{}^\circ -\theta )-\sin (270{}^\circ -\theta )\,\cos \theta $ is

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• If $\sin \theta =\frac{-4}{5}$ and $\theta $ lies in the third quadrant, then $\cos \frac{\theta }{2}=$

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• A, B, C are the angles of a triangle, then ${{\sin }^{2}}A+{{\sin }^{2}}B+{{\sin }^{2}}C-2\cos A\,\cos B\,\cos C=$

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• In $\Delta ABC,$ if $a=16,b=24$ and $c=20,$ then $\cos \frac{B}{2}=$

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• If $\sec \theta +\tan \theta =p,$then $\tan \theta $is equal to

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