Question

помогите пожалуйста умоляю!!!!!

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Answer 1

$1) \\\displaystyle\bf\\\sqrt{18} -6\sqrt{72}+\sqrt{50} =\sqrt{9\cdot2} -6\sqrt{36\cdot2}+\sqrt{25\cdot2} =\\\\=3\sqrt{2} -6\cdot6\sqrt{2} +5\sqrt{2} =8\sqrt{2} -36\sqrt{2} =-28\sqrt{2} \\\\2)\\\displaystyle\bf\\(\sqrt{3} +\sqrt{27} )\cdot\sqrt{3} =(\sqrt{3} +\sqrt{9\cdot3} )\cdot 3=(\sqrt{3} +3\sqrt{3})\cdot\sqrt{3} =\\\\=4\sqrt{3}\cdot\sqrt{3} =4\cdot3=12$