已知y²=3.14,(x-z)²=0.14,则(x+y-z)(x-y-z)=若(a-b-1)(a-b-3)=5,则(a-b-2)²=

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已知y²=3.14,(x-z)²=0.14,则(x+y-z)(x-y-z)=若(a-b-1)(a-b-3)=5,则(a-b-2)²=
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已知y²=3.14,(x-z)²=0.14,则(x+y-z)(x-y-z)=若(a-b-1)(a-b-3)=5,则(a-b-2)²=
已知y²=3.14,(x-z)²=0.14,则(x+y-z)(x-y-z)=
若(a-b-1)(a-b-3)=5,则(a-b-2)²=

已知y²=3.14,(x-z)²=0.14,则(x+y-z)(x-y-z)=若(a-b-1)(a-b-3)=5,则(a-b-2)²=
已知y²=3.14,(x-z)²=0.14,
则,y^2-(x-z)^2=3.14-0.14=3
[y+(x-z)][y-(x-z)]=3
(y+x-z)(y-x+z)=3
-(x+y-z)(x-y-z)=3
所以,(x+y-z)(x-y-z)=-3
若(a-b-1)(a-b-3)=5
则,(a-b)^2-4(a-b)+3=5
(a-b)^2-4(a-b)=2
那么,(a-b-2)²
=[(a-b)-2]^2
=(a-b)^2-4(a-b)+4
=2+4
=6

设a-b=X. X^2-4x-2=0 x=2+根号6或2-根号6
答案为6 (x+y-z)(x-y-z)=-3