问题 解答题

若|x+y-1|+(x-y+3)2=0,则(x+y)2009的值为多少?

答案

∵|x+y-1|+(x-y+3)2=0,

∴x+y-1=0且x-y+3=0,

解得x=-1,y=2.

∴(x+y)2009=(-1+2)2009=1.

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