Cos 22.5 градусов sin 3п/8 cos 3п/8

[latex]cos\frac{45}{2}*\frac{1}{2}*2sin\frac{3\pi}{8}cos\frac{3\pi}{8}=\\ =\sqrt{\frac{1+cos45}{2}}*\frac{1}{2}*sin\frac{3\pi}{4}=\\ =\sqrt{\frac{1+\frac{\sqrt{2}}{2}}{2}}*\frac{1}{2}*\frac{\sqrt{2}}{2}=\\ =\sqrt{\frac{2+\sqrt{2}}{4}}*\frac{\sqrt{2}}{4}=\\ =\sqrt{2+\sqrt{2}}*\frac{\sqrt{2}}{8}[/latex]