If x x x and y y y vary inversely to each other, and x = 7 x = 7 x = 7 when y = 12 y = 12 y = 12 , find y y y when x = 21 x = 21 x = 21 .

If the mean of $$ p, q, r $$ is $$ M $$ and $$ pq + qr + rp = 0 $$, then the mean of $$ p^2, q^2, r...

If $$ x $$ is an odd integer, which of the following statements is correct? ...

If $$\sqrt{5x + 9} + \sqrt{5x - 9} = 3(2 + \sqrt{2}),$$ then $$\sqrt{10x + 9} \text{ is equal to ...

The number of integer solutions of the equation $$ 2|x|(x^2 + 1) = 5x^2 $$ is: ...

If $$p^2 + q^2 - 29 = 2pq - 20 = 52 - 2pq$$, then the difference between the maximum and minimum po...

If $$ \cos(6\theta) = \sin(3\theta) $$, then the value of $$ \theta $$ is: ...