Explicație pas cu pas:
[tex]b)a = 3 \sqrt{5} - \sqrt{20} - 4 \sqrt{3} + \sqrt{12} \\ \\ a = 3 \sqrt{5} - 2 \sqrt{5} - 4 \sqrt{3} + 2 \sqrt{3} \\ \\ a = (3 \sqrt{5} - 2 \sqrt{5}) + ( - 4 \sqrt{3} + 2 \sqrt{3}) \\ \\ a = \sqrt{5} - 2 \sqrt{3} [/tex]
[tex]c)a = \sqrt{112} - 6 \sqrt{7} - \sqrt{108} + 5 \sqrt{3} \\ \\ a = 4 \sqrt{7} - 6 \sqrt{7} - 6 \sqrt{3} + 5 \sqrt{3} \\ \\ a = (4 \sqrt{7} - 6 \sqrt{7}) + ( - 6 \sqrt{3} + 5 \sqrt{3}) \\ \\ a = - 2 \sqrt{7} - \sqrt{3} [/tex]
