Current location - Training Enrollment Network - Mathematics courses - 20 12, the national mathematics volume of the college entrance examination, was finally selected as the absolute value of the question.
20 12, the national mathematics volume of the college entrance examination, was finally selected as the absolute value of the question.
The answer given to this question is not very good.

It should be understood this way.

F (x) ≤| x-4 |, that is | x+a |≤| x-4 |-| x-2 |

As shown in the figure, because | x+a | >;; =0

In order to make | x+a |≤| x-4 |-x-2 | meaningful, you must have | x-4 |-x-2 | = 0 and get x.

When 2

When x

Then calculate the result.

Actually this is the best algorithm! Do you agree?