Question

Найти силовое значение выражения

Answer 1

$1)frac{2x}{x+y}-frac{2x^{2}}{x^{2}+2xy+y^{2}}=frac{2x}{x+y}-frac{2x^{2}}{(x+y)^{2}}=frac{2x*(x+y)-2x^{2}}{(x+y)^{2}}=frac{2x^{2}+2xy-2x^{2}}{(x+y)^{2}}=frac{2xy}{(x+y)^{2}}\\2)1+frac{2y}{x-y}=frac{x-y+2y}{x-y}=frac{x+y}{x-y}\\3)frac{2xy}{(x+y)^{2}}*frac{x+y}{x-y}=frac{2xy}{x^{2}-y^{2}} \\4)frac{2xy}{x^{2}-y^{2}} =frac{2*(-1)*(-frac{1}{2})}{(-1)^{2}-(-frac{1}{2})^{2}}=frac{1}{frac{3}{4}}=1frac{1}{3}$