a

来源：学生作业帮助网编辑：六六作业网时间：2025/01/29 06:39:49

aaala-cl+lb-al-lc-al=c-a+b-a-(c-a)=b-a

a
a

a
la-cl+lb-al-lc-al
=c-a+b-a-(c-a)
=b-a

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