在平面直角坐标系中,如果L1与x轴平行,L2与y平行,如何求证k1k2=-1（k1,k2分别为y1,y2的斜率,即x的系
在平面直角坐标系中,如果L1与x轴平行,L2与y平行,如何求证k1k2=-1（k1,k2分别为y1,y2的斜率,即x的系数
原文如下：The lines y=m1x+c1 and y=m2x+c2 are perpendicular if and only if m1m2=-1.If the line l1 is horizontal and the line l2 is vertical,how do you show that m1m2=-1?
原文如下：The lines y=m1x+c1 and y=m2x+c2 are perpendicular if and only if m1m2=-1.If the line l1 is horizontal and the line l2 is vertical,how do you show that m1m2=-1?
可能相似的问题
你能帮帮他们吗
精彩回答