[tex] \sqrt{(2-3 \sqrt{3} )^{2}} +2*|3- \sqrt{13} |-7.5*(4- \sqrt{8} )^{2}+ \frac{6.4}{5-1.8} =\\=
|2-3 \sqrt{3} | +2*(\sqrt{13}-3) -7.5*(16+8-8 \sqrt{8} )+ \frac{6.4}{3.2} =\\=
3 \sqrt{3}-2 +2\sqrt{13}-6 -7.5*(24-8 \sqrt{8} )+ 2 =\\=
3 \sqrt{3} +2\sqrt{13}-6 -180+ 60\sqrt{8} =\\=
3 \sqrt{3} +2\sqrt{13}-186+ 60*2\sqrt{2} =\\=
3 \sqrt{3} +2\sqrt{13}-186+ 120\sqrt{2} [/tex]