Question

Помогите пж. Заранее спс

Answer 1

$\displaystyle 1) \frac{m^2}{5} -\frac{n^2}{14} = \frac{1}{70}*(14m^2 - 70 *\frac{n^2}{14} )  \\ 2) (\sqrt{5}+ \sqrt{3} )*(\sqrt{5} -\sqrt{3}) = 5 -3 =2 \\ \\  3) (\sqrt{3}- {2\sqrt{10} )} *(\sqrt{3} +2\sqrt{10} )=3-4*10=3-40 = -37$