5✓2* sin(3pi/8)* cos(3pi/8)
Помогите

[tex]5 \sqrt{2}sin \frac{3 \pi }{8} cos\frac{3 \pi }{8}= \frac{5 \sqrt{2}}{2} sin \frac{3 \pi }{4} = \frac{5 \sqrt{2}}{2} sin( \pi - \frac{\pi }{4}) =\frac{5 \sqrt{2}}{2} sin\frac{\pi }{4}=\frac{5 \sqrt{2}}{2}* \frac{ \sqrt{2} }{2} =5[/tex]