If the number represented by point C is x, when point C is on the number axis, where does | x + 1 | + | X-2 | get the minimum value? Write down the process of doing the problem. Write the arithmetic or the written form

If the number represented by point C is x, when point C is on the number axis, where does | x + 1 | + | X-2 | get the minimum value? Write down the process of doing the problem. Write the arithmetic or the written form

Interval [- 1,2]