Вычислите cos22°30'.

\[\cos{22{^\circ}}30^{'} = \sqrt{\frac{1 + \cos{45{^\circ}}}{2}} =\]

\[= \sqrt{\frac{1 + \frac{\sqrt{2}}{2}}{2}} = \sqrt{\frac{2 + \sqrt{2}}{4}} =\]

\[= \sqrt{\frac{2 + \sqrt{2}}{2}}\text{\ \ }\ \]