Question

Помогите пж. Заранее спс

Answer 1

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