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Solution: What is X and Y?
This kind of problem, to be honest, is a basic problem, but LZ needs a process, and it is estimated that the mathematical foundation is not very good. First, I will write down the answers.

X & gt=2 or x

why

I can only think of two explanations.

The absolute value is 1 and x >;; =2, because both sides are greater than 0, according to the function y = x 2 in x >; 0 is increasing function's principle (you can understand it as a number greater than 0, the larger the value, the larger the square, and vice versa), and you can square both sides of the inequality at the same time to get x2 >;; =4 Re-deformation (X-2)(X+2)>=0, so X-2 and X+2 have the same sign or one of them is 0. According to the same symbol (both positive and negative), X >;; 2 or x

This method, pure proof, generally does not require any understanding ability.

2, graphical method, draw an X axis, and then specify an origin, the meaning of absolute value is the distance from the point corresponding to the X axis to the origin. Just when the distance X=2 or X=-2 is equal to 2, look at the picture and you will know that if the distance is not less than 2, there is X >;; =2 or x

LZ, think again! Wish LZ success!