The solution of this kind of problem is fixed: we should combine the images and properties of direct proportional function and inverse proportional function;

(1) logarithmic proportional function: y=kx, when k >; 0, the function value y increases with the increase of x and k.

Situations that need to be discussed, such as in this example:

Solution: y=kx, when k >; 0, the function value y increases with the increase of x.

When x=-3 and y=-3k; When x=- 1, y =-k; So when -3

K<0, Y decreases with the increase of X; So when -3

So -3

K<0, the value range of function y is:-K.

Just use this format to express it.

If it is an inverse proportional function, the same is true; For example y = k/x, 2

When k>0, the function value y decreases with the increase of x; When x=2, y = k/2; When x=3, y=k/3 (that is, x increases from 2 to 3, and the function value y decreases from k/2 to k/3, so 2

That's all; You can make up the rest yourself. I hope you can understand. I wish you progress in your study.