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请问一下y、z小于0,x大于0,求|x-y|+|y-z|+|x-z|+|y+z|,

题目详情
请问一下y、z小于0,x大于0,求|x-y|+|y-z|+|x-z|+|y+z|,
▼优质解答
答案和解析
当y大于z
则|x-y|+|y-z|+|x-z|+|y+z|
=x-y+y-z+x-z-y-z
=2x-3z-y
当z>y
|x-y|+|y-z|+|x-z|+|y+z|
=x-y-y+z+x-z-y-z
=2x-2y-z