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Problem 350

AMC 12 late, AIME early

Algebra Difficulty 4.7 Find the answer

9. The function $y=|x+2|+|1-x|+1$ is an increasing function for $x$ , then $x$ must belong to the interval ( )
(A) $(-\infty,-2]$
(B) $[-2,0]$
(C) $[0,+\infty$ )
(D) $(-\infty, 0]$

Your answer

Official solution

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic, difficulty and ordering added by this site.