已知2x-y=2014,求式子[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y_数学解答

已知2x-y=2014,求式子[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y

人气：489 ℃　时间：2020-01-27 10:15:40

解答

[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y
=(x^2+y^2-x^2-y^2+2xy+2yx-2y^2)/4y
=(4xy-2y^2)/4y
=(2xy-y^2)/2y
=[y(2x-y)]/2y
=(2x-y)/2
=2014/2
=1007