Because x

2 If 2≤x≤a has only three integer solutions, then the range of A is (4

According to the problem, the solution of X is 2,3,4, so A can be equal to 4 and less than 5.

3 It is known that the positive integer solution of inequality 4x-a≤0 is 1, 2,3. Find the value range of a ..

X

It is known that the positive integer solution of the inequality 5x-a≤0 about x is 1, 2, 3, 4. Find the range of a ..

4 < = a/5 & lt； 5, so you get 20.

This kind of problem is mainly to find the boundary, and the thinking must be clear.