Find the smallest positive \alpha (in degrees) for which all the numbers
\cos \alpha, \cos 2 \alpha, \ldots, \cos 2^{n} \alpha, \ldots
are negative.
Find the smallest positive \alpha (in degrees) for which all the numbers
\cos \alpha, \cos 2 \alpha, \ldots, \cos 2^{n} \alpha, \ldots
are negative.