Răspuns:
a = -6
Explicație pas cu pas:
[tex]a=\sqrt{24}\cdot \Big(\frac{3}{\sqrt{2}} - \frac{2}{\sqrt{3}} + \frac{1}{\sqrt{6}}\Big)-2(3\sqrt{3}-2\sqrt{2}+4) \\\\ = 2\sqrt{6}\cdot \frac{3\sqrt{3} - 2\sqrt{2} + 1}{\sqrt{6}} - 6\sqrt{3} + 4\sqrt{2} - 8\\\\ = 2(3\sqrt{3}-2\sqrt{2}+1)-6\sqrt{3} + 4\sqrt{2} - 8 \\\\= 6\sqrt{3} - 4\sqrt{2}+2-6\sqrt{3}+4\sqrt{2}-8 \\\\= 2-8\\\\ = -6\implies a \in \mathbb{Q}[/tex]