【要点解析】(一)反比例函数的定义定义:一般地,如果两个变量x、y之间的关系可以表示成y=kx(k为常数,k≠0)的形式,那么称y为x的反比例函数.1.自变量x与因变量y都不能为0.利用k=xy可确定反比例函数解析式.只要有一对对应值或图象上一个点的坐标,即可求出k的值,从而确定其解析式. [Point analysis] (a) definition of inverse proportion function Definition: Generally, if the relationship between two variables x, y can be expressed as y = kx (k is a constant, k ≠ 0), then y is called x Inverse Proportional Function: 1. The argument x and the dependent variable y cannot be 0. The inverse scale function can be determined by using k=xy. The expression can be obtained as long as there is a pair of corresponding values ​​or the coordinates of a point on the image. To determine its analytical formula.