Question

Найти силовое значение выражения

Answer 1

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