已知xy<0,化简 x根号下-y^3/x^2

问题描述:

已知xy<0,化简 x根号下-y^3/x^2

xy<0
-xy>0
√-y^3/x^2
=√-y(y^2/x^2)
要使得根号有意义,则y必须<0
则原式=-(y/x)*√-y