Упростить выражение[latex] \frac{1- \sqrt{10} }{ \sqrt{2} + \sqrt{5} } + \frac{7}{2 \sqrt{2}+1 }-(11- 5\sqrt{5})(2+ \sqrt{5})[/latex]

[latex]\frac{1-\sqrt{10}}{\sqrt{2}+\sqrt{5}}+\frac{7}{2\sqrt{2}+1}-(11-5\sqrt{5})(2+\sqrt{5})=\\\\ \frac{(\sqrt{5}-\sqrt{2})(1-\sqrt{10})}{3}+\frac{7(2\sqrt{2}-1)}{7}-(\sqrt{5}-3)=\\\\ \frac{21\sqrt{5}-42\sqrt{2}}{21}+\frac{42\sqrt{2}-21}{21}-\frac{21(\sqrt{5}-3)}{21}=\\\\ \frac{42}{21}=2[/latex]