trigonometry

Related Questions

• In a $\Delta ABC,$ if $\frac{b+c}{11}=\frac{c+a}{12}=\frac{a+b}{13}$ , then $\cos C=$

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• If $\frac{\pi }{2}<\alpha <\pi ,\,\text{ }\pi <\beta <\frac{3\pi }{2};$ $\sin \alpha =\frac{15}{17}$ and $\tan \beta =\frac{12}{5}$, then the value of $\sin (\beta -\alpha )$ is

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• Values of $\theta (0<\theta <{{360}^{o}})$ satisfying $\text{cosec}\theta +2=0$ are

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• If the angles of elevation of two towers from the middle point of the line joining their feet be 60° and 30° respectively, then the ratio of their heights 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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