The two projectiles are projected with the same initial velocities at the \( 15^\circ \) and \( 30^\circ \) with respect to the horizontal. The ratio of their ranges is \( 1:x \). The value of \( x \) is:
\( \sqrt{2} \)
\( \sqrt{3} \)
\( 2\sqrt{3} \)
\( \frac{1}{\sqrt{2}} \)