[tex](2\sqrt{7}+3\sqrt{6})(5\sqrt{2}+4\sqrt{3}) \\\\\\ \begin{array}{lllllll} 10\sqrt{14}&+&15\sqrt{12}&+&8\sqrt{21}&+&12\sqrt{18}\\\\ &&15\sqrt{2^2\cdot 3}&&&&12\sqrt{3^2\cdot 2}\\\\ &&15\cdot 2\sqrt{3}&&&&12\cdot 3\sqrt{2}\\\\ &&30\sqrt{3}&&&&36\sqrt{2}\\\\ 10\sqrt{14}&+&30\sqrt{3}&+&8\sqrt{21}&+&36\sqrt{2}\\\\ 10\sqrt{14}&+&8\sqrt{21}&+&30\sqrt{3}&+&36\sqrt{2} \end{array}[/tex]
