Réponse:
7-
[tex] 7 - \sqrt{12} - 8 + 3 \sqrt{27} = - 1 - 2 \sqrt{3} + 9 \sqrt{3} = 7 \sqrt{3} - 1 \: \\ a = - 1 \: \: b \sqrt{c} = 7 \sqrt{3} [/tex]
[tex] 3 \sqrt{50} - \sqrt{49} + 2 \sqrt{8} = 15 \sqrt{2} - 7 + 4 \sqrt{2} = 19 \sqrt{2 } - 7 \\ a = - 7 \\ \\ b \sqrt{c} = 19 \sqrt{2 } [/tex]
