Răspuns:
[tex]a)x = \sqrt{8} - 4 \sqrt{50} - \sqrt{27} = 2 \sqrt{2} - 20 \sqrt{2} - 3 \sqrt{3 } = \\ - 18 \sqrt{2} - 3 \sqrt{3} [/tex]
[tex]y = 3 \sqrt{48} - \sqrt{98} - 2 \sqrt{75} = 12 \sqrt{3} - 21\sqrt{2 } - 10 \sqrt{3} = \\ 2 \sqrt{3 } -21 \sqrt{2} [/tex]
[tex]x + y = - 39\sqrt{3} - 25 \sqrt{2} \\ y - x = 5 \sqrt{3} + 11 \sqrt{2} [/tex]
[tex]b)x = 5 \sqrt{8} - \sqrt{20} - 4 \sqrt{45} = 10 \sqrt{2} - 2 \sqrt{5} - 12 \sqrt{5} = 10 \sqrt{2} - 14 \sqrt{5} [/tex]
[tex]y = 7 \sqrt{18} - \sqrt{125} - 3 \sqrt{98} = 21 \sqrt{2} - 5 \sqrt{5} - 21\sqrt{2} = \\ 14 \sqrt{2 } - 5 \sqrt{5} [/tex]
[tex]x + y = 24 \sqrt{2} - 19 \sqrt{5} \\ y - x = 4 \sqrt{2} + 9 \sqrt{5} [/tex]