第1743题：葫芦图形
能产生上图中葫芦形的函数是( )
A. x+y=xy3x+y=\sqrt[3]{xy}x+y=3√xy
B. x2+y2=(xy)2x^2+y^2=(xy)^2x2+y2=(xy)2
C. x2−y2=xy3x^2-y^2=\sqrt[3]{xy}x2−y2=3√xy
D. x2+y2=xy3x^2+y^2=\sqrt[3]{xy}x2+y2=3√xy
