1.已知2x+y=4,求这个整式[(x+y)^2-(x-y)^2-2y(x-1/2 y)]÷4y的值

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1.已知2x+y=4,求这个整式[(x+y)^2-(x-y)^2-2y(x-1/2 y)]÷4y的值

1.已知2x+y=4,求这个整式[(x+y)^2-(x-y)^2-2y(x-1/2 y)]÷4y的值
1.已知2x+y=4,求这个整式[(x+y)^2-(x-y)^2-2y(x-1/2 y)]÷4y的值

1.已知2x+y=4,求这个整式[(x+y)^2-(x-y)^2-2y(x-1/2 y)]÷4y的值
(x+y)^2-(x-y)^2=4xy
原式=(4xy-2xy+y^2)/4y=(2xy+y^2)/4y=(2x+y)/4=1

[(x+y)^2-(x-y)^2-2y(x-1/2 y)]÷4y=[x^2+2xy+y^2-x^2+2xy-y^2-2xy+y^2]÷4y=[2xy+y^2]÷4y=[2x+y]÷2=2

^2是指平方吗