[tex]a = 7 \sqrt{2} - 2 \sqrt{15}( \sqrt{30} - \sqrt{60}) + \sqrt{24}( \frac{15}{ \sqrt{3} } - \frac{7}{ \sqrt{2} }) \\ \\ a = 7 \sqrt{2} - 2 \sqrt{15}( \sqrt{30} - 2 \sqrt{15}) + 2 \sqrt{6}( \frac{15}{ \sqrt{3} } - \frac{7}{ \sqrt{2} }) \\ \\ a = 7 \sqrt{2} - 2 \sqrt{15}( \sqrt{30} - 2 \sqrt{15}) + 2 \sqrt{6}( \frac{15 \sqrt{3} }{3} - \frac{7 \sqrt{2} }{2}) \\ \\ a = 7 \sqrt{2} - 2 \sqrt{15}( \sqrt{30} - 2 \sqrt{15}) + 2 \sqrt{6}(5 \sqrt{3} - \frac{7 \sqrt{2} }{2}) \\ \\ a = 7 \sqrt{2} - 30 \sqrt{2} + 60 + 30 \sqrt{2} - 14 \sqrt{3} \\ \\ a = (7 \sqrt{2} - 30 \sqrt{2} + 30 \sqrt{2}) + 60 - 14 \sqrt{3} \\ \\ a = 7 \sqrt{2} + 60 - 14 \sqrt{3} [/tex]
