已知
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2(√X+√Y-1+ √Z-2)=X+Y+Z,求X,Y,Z
參考答案:2[√X+√(Y-1)+ √(Z-2)]=X+Y+Z,
(X-2√X+1)+[Y-1-2√(Y-1)+1]+ [Z-2+2√(Z-2)+1]=0
(√X-1)^2+[√(Y-1)-1]^2+[√(Z-2)-1]^2=0
(√X-1)^2>=0,[√(Y-1)-1]^2>=0,[√(Z-2)-1]^2>=0
√X-1=0,(√(Y-1)-1=0,,(√(Z-2)-1=0
X=1,Y=2,Z=3