我们知道,一次函数y=kx+6(k、b是常数,k≠0)的图象是经过点(0,6)和点(-b/k,0)的一条直线,也可以说,其图象是经过点(0,6)且平行于直线y=kx的一条直线.但在实际生活中,一次函数的图象就不一定是直线了.这是因为在实际生活中,函数自变量的取值范围改变了,缩小了.另外在一些问题中,由于自变量所取的不同数值,使得表达变量关系 We know that the image of a function y=kx+6 (k, b is a constant, k≠0) is a straight line passing through the point (0,6) and the point (-b/k,0). It can also be said that The image is a line passing through the point (0,6) and parallel to the line y=kx. But in real life, the image of a function is not necessarily a straight line. This is because in real life, the function itself The variable’s range of values ​​has changed and has shrunk. In addition, due to the different values ​​taken by the independent variables, expression variables