Zgjidh 4sum_x=3^10left(tan(pi/x)/xright)

$$4 \sum_{ x=3 }^{ 10 } \left( \frac{ \tan ( \frac{ \pi }{ x } ) }{ x } \right)$$

Vlerëso

$$\frac{\sqrt[4]{5}\left(1008\cos(\frac{\pi }{7})\cos(\frac{\pi }{9})\sqrt{\frac{5\left(\sqrt{5}-2\right)}{16}}+2520\cos(\frac{\pi }{7})\cos(\frac{\pi }{9})\sqrt{\sqrt{5}-2}+315\sqrt{2}\times 5^{\frac{3}{4}}\cos(\frac{\pi }{7})\cos(\frac{\pi }{9})+980\sqrt{3}\times 5^{\frac{3}{4}}\cos(\frac{\pi }{7})\cos(\frac{\pi }{9})+280\times 5^{\frac{3}{4}}\sin(\frac{\pi }{9})\cos(\frac{\pi }{7})+315\times 5^{\frac{3}{4}}\cos(\frac{\pi }{7})\cos(\frac{\pi }{9})+360\times 5^{\frac{3}{4}}\sin(\frac{\pi }{7})\cos(\frac{\pi }{9})\right)}{3150\cos(\frac{\pi }{7})\cos(\frac{\pi }{9})}\approx 5.049559983$$