a)
[tex]12\sqrt{2}=\sqrt{144}\sqrt{2}=\sqrt{288} \\ \\ 4\sqrt{3}=\sqrt{16}\sqrt{3}=\sqrt{48} \\ \\ 3\sqrt{3}=\sqrt{9}\sqrt{3}=\sqrt{27} \\ \\ -2\sqrt{2}=-\sqrt{4}\sqrt{2}=-\sqrt{8} \\ \\ -6\sqrt{7}=-\sqrt{36}\sqrt{7}=\sqrt{252} \\ \\ 1,5\sqrt{7}=\sqrt{2,25}\sqrt{7}=\sqrt{15,75}[/tex]
b)
[tex]\sqrt{300}=\sqrt{100}\sqrt{3}=10\sqrt{3} \\ \\ \sqrt{3x^2}=\sqrt{x^2}\sqrt{3}=|x|\sqrt{3}[/tex]
