trigonometry

Related Questions

• If $5\cos 2\theta +2{{\cos }^{2}}\frac{\theta }{2}+1=0,-\pi <\theta <\pi $, then $\theta =$

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• If A is the area and 2s the sum of 3 sides of triangle, then

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• The value of $\cos 12{}^\circ +\cos 84{}^\circ +\cos 156{}^\circ +\cos 132{}^\circ $ is

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• $\cos \frac{\pi }{7}\cos \frac{2\pi }{7}\cos \frac{4\pi }{7}=$

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• If in the $\Delta ABC,AB=2BC$ , then $\tan \frac{B}{2}:\cot \left( \frac{C-A}{2} \right)$

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