Помогите преобразовать это 8sin²(π/8)cos²(π/8)

[latex]8 sin^{2} \frac{ \pi }{8} * cos^{2} \frac{ \pi }{8} =2*(4sin ^{2} \frac{ \pi }{8}* cos^{2} \frac{ \pi }{8} )=2*(2 sin \frac{ \pi }{8}*cos \frac{ \pi }{8} ) ^{2} =[/latex] [latex]=2*(sin(2* \frac{ \pi }{8} )) ^{2} =2(sin \frac{ \pi }{4} ) ^{2} =2*( \frac{ \sqrt{2} }{2} ) ^{2} =2* \frac{2}{4} =1[/latex]