trigonometry

Related Questions

• The angle of elevation of a tower at a point distant d meters from its base is 30°. If the tower is 20 meters high, then the value of d is

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• The equation ${{\sec }^{2}}\theta =\frac{4xy}{{{(x+y)}^{2}}}$is only possible when

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• If $2y\,\cos \theta =x\sin \,\theta \text{ and }2x\sec \theta -y\,\text{cosec}\,\theta =3,$ then ${{x}^{2}}+4{{y}^{2}}=$

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• If $\Delta ={{a}^{2}}-{{(b-c)}^{2}}$ , where $\Delta $ is the area of triangle $ABC$ , then tan A is equal to

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

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