Question

6. Спростіть вираз:
СРОЧНО!!!!

Answer 1

$\displaystyle\bf\\1)\\\\\frac{1}{\sqrt{x} -3\sqrt{y} } -\frac{1}{\sqrt{x} +3\sqrt{y} } =\frac{\sqrt{x} +3\sqrt{y}-\sqrt{x} +3\sqrt{y} }{(\sqrt{x} -3\sqrt{y} )\cdot(\sqrt{x} +3\sqrt{y} )} =\\\\\\=\frac{6\sqrt{y} }{(\sqrt{x} -3\sqrt{y})\cdot(\sqrt{x} +3\sqrt{y} )} \\\\\\2)\\\\\frac{6\sqrt{y} }{(\sqrt{x} -3\sqrt{y})\cdot(\sqrt{x} +3\sqrt{y} )} :\frac{3 }{\sqrt{x} +3\sqrt{y} } =$

$\displaystyle\bf\\=\frac{6\sqrt{y} }{(\sqrt{x} -3\sqrt{y})\cdot(\sqrt{x} +3\sqrt{y} )} \cdot\frac{\sqrt{x} +3\sqrt{y} }{3} =\frac{2\sqrt{y} }{\sqrt{x} -3\sqrt{y} }$