trigonometry

Related Questions

• The value of $\cos 15{}^\circ -\sin 15{}^\circ $is equal to

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• If $4{{\sin }^{4}}x+{{\cos }^{4}}x=1,$then $x =$

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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 ${{\sec }^{2}}\theta =\frac{4}{3}$, then the general value of $\theta $is

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• $\frac{\cos 9{}^\circ +\sin 9{}^\circ }{\cos 9{}^\circ -\sin 9{}^\circ }=$

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