x=2\sin60-\frac{\cos45}{\sin45}-\tg30=
2*\frac{\sqrt{3}}{2}-\frac{\frac{\sqrt{2}}{2}}{\frac{\sqrt{2}}{2}}-\frac{\sqrt{3}}{3}=
\sqrt{3}-\frac{\sqrt{2}}{2}*\frac{2}{\sqrt{2}}-\frac{\sqrt{3}}{3}=\sqrt{3}-1-\frac{\sqrt{3}}{3}=\sqrt{3}-\frac{\sqrt{3}}{3}-1=(1-\frac{1}{3})\sqrt{3}-1=\frac{2}{3}\sqrt{3}-1=-1+\frac{2}{3}\sqrt{3}
(-1+\frac{2}{3}\sqrt{3})^2=(-1)^2+2*(-1)*\frac{2}{3}\sqrt{3}+(\frac{2}{3}\sqrt{3})^2=1-\frac{4}{3}\sqrt{3}+\frac{4}{9}*3=1-\frac{4}{3}\sqrt{3}+\frac{4}{3}=2\frac{1}{3}-\frac{4}{3}\sqrt{3}=2\frac{1}{3}-1\frac{1}{3}\sqrt{3}