从几何意义看洛必达法则

Geometric Meaning of L'Hspital's Rule

把0/0型未定式极限看作是一个参变量函数的割线的极限,就能在几何意义上观察到其实质是参变量方程曲线在原点的切线斜率,从而能更好地理解其含义;从参变量方程的角度,也可证明洛必达法则的正确性.

L＇Hospital＇s rule can be viewed as a consequence of the CauChy mean value theorem. However, the limit of the type of 0 by 0 can be regarded also as the limit of the secants of a parametric function, which is, in the geometric sense, the tangent of the curve at the origin. This observation leads to a better understanding of the L ＇Hospital rule in geometry, and provides another proof of the rule from the viewpoint of parametric function.