The general solution of $ 2 \cos 4x + \sin^2 2x $= 0 is
The expression $ \frac{2 \tan A}{1 - \cot A} + \frac{2 \cot A}{1 - \tan A} $ can be written as
If $ \cos A = m \cos B $ and $ \cot \left( \frac{A+B}{2} \right) = \lambda \tan \left( \frac{B-A}{2} \right), $ then $ \lambda \text{ is equal to} $
If a number $ n $ is chosen at random from the set $\{11, 12, 13, ..., 30\}\,$ then, the probability that $ n $ is neither divisible by 3 nor divisible by 5, is
The lines $ \frac{x-1}{2} = \frac{y-4}{4} = \frac{z-2}{3} \quad \text{and} \quad \frac{1-x}{1} = \frac{y-2}{5} = \frac{3-z}{a} \quad \text{are perpendicular to each other, then} \ a \ \text{equals to} $