# Lomené výrazy

 (a) $\dfrac{1}{x}+\dfrac{1}{y}>0$ (b) $\dfrac{xy}{y-x+4}\ge0$ (c) $\dfrac{3x-y+6}{2x+y-1}\ge0$ (d) $\dfrac{x^2-2y}{y^2-2x}\ge0$ (e) $\dfrac{x^2y}{1-x^2-y^2}\ge0$ (f) $\dfrac{x^2+2x+y^2}{x^2-2y+y^2}<0$