Triangolo equilatero: differenze tra le versioni

h=\sqrt{l^2-{\leftright(\frac{l}{2}}\rightleft)^2}=\sqrt{l^2-{\frac{l^2}{4}}}=\sqrt{\frac{4l^2-l^2}{4}}=\sqrt{\frac{3l^2}{4}}=\frac{\sqrt{l^2}\times{\sqrt{3}}}{\sqrt{4}}=\frac{{l}\times{\sqrt{3}}}{2} = \frac{l}{2}\sqrt{3}