Explicație pas cu pas:
[tex]a)2 \sqrt{6} + 3 \sqrt{3} - (5 \sqrt{6} - 3 \sqrt{3}) + ( - 3 \sqrt{6} - 9 \sqrt{3}) = \\ \\ 2 \sqrt{6} + 3 \sqrt{3} - 5 \sqrt{6} + 3 \sqrt{3} - 3 \sqrt{6} - 9 \sqrt{3} = \\ \\ (2 \sqrt{6} - 5 \sqrt{6} - 3 \sqrt{6}) + (3 \sqrt{3} + 3 \sqrt{3} - 9 \sqrt{3}) = \\ \\ (2 - 5 - 3) \sqrt{6} + (3 + 3 - 9) \sqrt{3} = \\ \\ (2 - 8) \sqrt{6} + (6 - 9) \sqrt{3} = \\ \\ - 6 \sqrt{6} - 15 \sqrt{3} [/tex]
[tex]b)(3 \sqrt{2} - 2 \sqrt{3}) + ( - 4 \sqrt{2} - 3 \sqrt{3}) - (6 \sqrt{2} - 5 \sqrt{3}) = \\ \\ 3 \sqrt{2} - 2 \sqrt{3} - 4 \sqrt{2} - 3 \sqrt{3} - 6 \sqrt{2} + 5 \sqrt{3} = \\ \\ (3 \sqrt{2} - 4 \sqrt{2} - 6 \sqrt{2}) + ( - 2 \sqrt{3} - 3 \sqrt{3} + 5 \sqrt{3}) = \\ \\ (3 - 4 - 6) \sqrt{2} + ( - 2 - 3 + 5) \sqrt{3} = \\ \\ (3 - 10) \sqrt{2} + ( - 5 + 5) \sqrt{3} = \\ \\ - 7 \sqrt{2} + 0 \sqrt{3} = \\ \\ - 7 \sqrt{2} [/tex]
