Объяснение:

[tex](\frac{1}{\sqrt{35} -7} -\frac{1}{\sqrt{35}+7 })*\frac{\sqrt{8} }{\sqrt{2} }=\frac{\sqrt{35}+7-\sqrt{35}+7 }{(\sqrt{35}-7)*(\sqrt{35}+7) } *\sqrt{\frac{8}{2} } =\frac{14}{(\sqrt{35})^2*-7^2 }*\sqrt{4} =\\ =\frac{14}{35-49}*2=\frac{14}{-14} *2=-1*2=-2.[/tex]