若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4确定XYZ大若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4.试确定XYZ大小关系

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若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4确定XYZ大若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4.试确定XYZ大小关系

若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4确定XYZ大若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4.试确定XYZ大小关系
若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4确定XYZ大
若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4.试确定XYZ大小关系

若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4确定XYZ大若实数X.Y.Z满足Y+Z=3X^2-4X+6 Y-Z=X^2-4X+4.试确定XYZ大小关系
y>=z>x
Y+Z=3X^2-4X+6 (1)
Y-Z=X^2-4X+4 (2)
由(2)得Y-Z=(X-2)^2>=0
即y>=z
(1)-(2)得2Z=2X^2+2
即Z=X^2+1>X

z-y=4-4x+x^2=(2-x)^2≥0,z≥y
两式y+z=6-4x+3x^2,z-y=4-4x+x^2相减,得y=1+x^2,y-x=x^2-x+1=(x-1/2)^2+3/4>0,y>x
故x

y大于或等于z大于x

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