trigonometry

Related Questions

• In a $\Delta ABC$ , $a,\ b,\ A$ are given and ${{c}_{1}},\ {{c}_{2}}$ are two values of the third side c. The sum of the areas of two triangles with sides $a,\ b,\ {{c}_{1}}$ and $a,b,\ {{c}_{2}}$ is

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

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• $\cot \frac{A+B}{2}$. $\tan \frac{A-B}{2}=$

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• A flag-staff of 5 m high stands on a building of 25 m high. At an observer at a height of 30 m. The flag-staff and the building subtend equal angles. The distance of the observer from the top of the flag-staff is

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• If the radius of the circumcircle of an isosceles triangle $PQR$ is equal to $PQ(=PR),$then the angle P is

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