m=2-sqrt(3)
m.(4-m).(2-m)/sqrt(3)
\(m.(4-m).(2-m)/sqrt(3)\\~\\ =\frac{m.(4-m).(2-m)}{\sqrt3}\\ \mbox{sub in }m=2-\sqrt3\\ =\frac{(2-\sqrt3)(4-(2-\sqrt3)).(2-(2-\sqrt3))}{\sqrt3}\\ =\frac{(2-\sqrt3)(2+\sqrt3).\sqrt3}{\sqrt3}\\ =(2-\sqrt3)(2+\sqrt3)\\ =4-3\\ =1\)