1)
[tex] \sqrt{8} = \sqrt{4 \times 2} = \sqrt{4} \times \sqrt{2} = 2 \sqrt{2} [/tex]
[tex] \sqrt{18} = \sqrt{9 \times 2} = 3 \sqrt{2} [/tex]
[tex] \sqrt{50} = \sqrt{25 \times 2} = 5\sqrt{2} [/tex]
Réduisons G.
[tex] \sqrt{50} + \sqrt{18} -2 \sqrt{8} = \sqrt{25 \times 2} + \sqrt{9 \times 2} -2 \sqrt{4 \times 2} \\ = 5 \sqrt{2} +3 \sqrt{2} -4\sqrt{2} \\ = 4 \sqrt{2} [/tex]
2)
[tex] \sqrt{12} - 7 \sqrt{27} + \sqrt{3} = \sqrt{4 \times 3} - 7 \sqrt{9 \times 3} + \sqrt{3} \\ = 2 \sqrt{3} - 21 \sqrt{3} + \sqrt{3} \\ = - 18 \sqrt{3} [/tex]
