The solution of parametric inequality is the solution of binary inequality, and the image method is the most intuitive.

Example: Solving Inequality ax

Solution: when a = 0, the inequality holds, that is, x ∈ r at this time;

When a > 0, available: x

When a < 0, we can get: x > 2/a, that is, in two or three quadrants on the (x, a) plane, the solution region is an infinite region with hyperbola ax = 2 or more;

Axis a should also be in the solution area.

Combine the above three sets to get the solution set.