Among the angles 30°, 36°, 45°, 50° one angle cannot be an exterior angle of a regular polygon. The angle is

The numerical value of $$1+\frac{1}{\cot^{2}63^{\circ}}-\sec^{2}27^{\circ}+\frac{1}{\sin^{2}63^{\circ}}-cosec^{2}27^{\circ}$$ is

If x ($$\sin$$ 60) $$\tan^{2}$$ 30° - $$\tan$$ 45° = cosec 60° $$\cot$$ 30° - $$\sec^{2}$$ 45°, then x =

When a pendulum of length 50 cm oscillates, it produces an arc of 16 cm. The angle so formed in degree measure is (approx)

If $$a=\frac{2+\sqrt{3}}{2-\sqrt{3}}$$ and $$b=\frac{2-\sqrt{3}}{2+\sqrt{3}}$$, then the value of $$a^2+b^2+a \times b$$ is