Răspuns:
Explicație pas cu pas:
a)
[tex]3\sqrt{10} - 2(4\sqrt{10} + 3) + 5\sqrt{10} =\\= 3\sqrt{10} - 8\sqrt{10} - 6 + 5\sqrt{10} =\\= - 5\sqrt{10} - 6 + 5\sqrt{10} =\\= -6[/tex]
b)
[tex]-7(3\sqrt{2} + \sqrt{3} ) + 3(\sqrt{8} + \sqrt{12})=\\= -21\sqrt{2} + 7\sqrt{3} + 3(2\sqrt{2} + 2\sqrt{3} )=\\= -21\sqrt{2} + 7\sqrt{3} + 6\sqrt{2} + 6\sqrt{3} =\\= -15\sqrt{2} + 13\sqrt{3}[/tex]
