已知:(x+2)2+|y+1|=0,求5xy2-{2x2y-[3xy2-(4xy2-2x2y)]}的值

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已知:(x+2)2+|y+1|=0,求5xy2-{2x2y-[3xy2-(4xy2-2x2y)]}的值
已知:(x+2)2+|y+1|=0,求5xy2-{2x2y-[3xy2-(4xy2-2x2y)]}的值

已知:(x+2)2+|y+1|=0,求5xy2-{2x2y-[3xy2-(4xy2-2x2y)]}的值
(x+2)2+|y+1|=0,
则x+2=0,y+1=0
则x=-2,y=-1
5xy2-{2x2y-[3xy2-(4xy2-2x2y)]}
=5xy²-2x²y+3xy²-4xy²+2x²y
=4xy²
=4×(-2)×(-1)²
=-8

x+2=0,x=-2
y+1=0,y=-1
5xy^2-{2x^2y-[3xy^2-(4xy^2-2x^2y)]}
=-10-{-8-[-6-(-8-8)]}
=8

x+2=0 x=-2
y+1=0 y=-1
5xy²-{2x²y-[3xy²-[4xy²-2x²y]]]
=4xy²=-8

x+2=0且y+1=0所以x=-2 y=-1 后面的那个化简的4xy2 带入x y 结果-8

因为|y+1|>=0,(x+2)2>=0
为保证两者之和等于0,所以
只能是|y+1|=0,(x+2)2=0
所以y=-1,x=-2
代入式中,得
-8

(x+2)2+|y+1|=0,
则x+2=0,y+1=0
则x=-2,y=-1
5xy2-{2x2y-[3xy2-(4xy2-2x2y)]}
=5xy²-2x²y+3xy²-4xy²+2x²y
=4xy²-4x²y
=4×(-2)×(-1)²-4×(-2)²×(-1)
=8

-8