已知(x-2)^2+|y+1|=0,求5xy^2-[2x^2y-(3xy^2-2x^2y)]的值

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已知(x-2)^2+|y+1|=0,求5xy^2-[2x^2y-(3xy^2-2x^2y)]的值

已知(x-2)^2+|y+1|=0,求5xy^2-[2x^2y-(3xy^2-2x^2y)]的值
已知(x-2)^2+|y+1|=0,求5xy^2-[2x^2y-(3xy^2-2x^2y)]的值

已知(x-2)^2+|y+1|=0,求5xy^2-[2x^2y-(3xy^2-2x^2y)]的值
(x-2)^2+|y+1|=0
绝对值和平方大于等于0,相加等于0,若有一个大于0,则另一个小于0,不成立
所以两个都等于0
所以x-2=0,y+1=0
x=2,y=-1
5xy^2-[2x^2y-(3xy^2-2x^2y)]
=5xy^2-2x^2y+(3xy^2-2x^2y)
=5xy^2-2x^2y+3xy^2-2x^2y
=8xy^2-4x^2y
=4xy(2y-x)
=4*2*(-1)*[2*(-1)-2]
=-8*(-4)
=32

x-2=0,y+1=0
x=2,y=-1
5xy^2-[2x^2y-(3xy^2-2x^2y)]
=5xy^2-2x^2y+3xy^2-2x^2y
=8xy^2-4x^2y
=4xy(2y-x)
=4*2*(-1)*(-2-2)
=32