如果2x-y=10,求代数式[(x2次+y2次)-(x-y)2次+2y(x-y)]÷4y的值.如果2x-y=10,求代数式[(x^2+y^2)-(x-y)^2+2y(x-y)]÷4y的值。

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如果2x-y=10,求代数式[(x2次+y2次)-(x-y)2次+2y(x-y)]÷4y的值.
如果2x-y=10,求代数式[(x^2+y^2)-(x-y)^2+2y(x-y)]÷4y的值。

[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y=[(x^2+y^2)-(x^2+y^2-2xy+2y(x-y)]/4y=[2xy+2y(x-y)]/4y=[2y(x+x-y)]/4y=[2y(2x-y)]/4y=20y/4y=5

[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y
=(x^2+y^2-x^2+2xy-y^2+2xy-2y^2)/4y
=(4xy-2y^2)/4y
=x-1/2y
=1/2(2x-y)
=1/2*10
=5

[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y
=(x^2+y^2-x^2+2xy-y^2+2xy-2y^2)/4y
=(4xy-2y^2)/4y
=x-1/2y
=1/2(2x-y)
=1/2*10
=5