一 引言 单值函数即对于自变量在定义域内的每一个值,函数只有一个确定的值与之对应时,这种函数称为单值函数。例如:y=x~3,y=Sinx,y=Logx等,都是单值函数。将其分析式当作曲线的方程,并把自变量与因变量的值作为点的横座标与纵座标,就可以绘成曲线,这就是单值函数的图示法(即函数图形)。从几何观 An introduction The single value function that is independent of variables in the domain of each value, the function only has a certain value corresponding to this function is called a single value function. For example: y = x ~ 3, y = Sinx, y = Logx, etc., are single-valued functions. The analytic equation as a curve, and the independent variables and dependent variable values ​​as the point of abscissa and ordinate, you can draw a curve, which is a single value function of the icon (that is, function graphics). From the geometric perspective