20 15 Hohhot senior high school entrance examination mathematics multiple-choice question 10.
Analysis: analyze from two situations: x < 0 and x > 0, and simplify the function relationship before determining the function image.
Answer:
Solution: when x < 0, the resolution function is: y=-x-2, and the function image is: b, d; when x > 0, the resolution function is: y=x+2, and the function image is: a, c, d, so D is selected.