(x-2y)2n÷(2y-x)2n-1+(2x-y)(-2x-y)+(x-y)(-x+y)

问题描述:

(x-2y)2n÷(2y-x)2n-1+(2x-y)(-2x-y)+(x-y)(-x+y)

原式=(2y-x)2n÷(2y-x)2n-1+(y2-4x2)-(x2-2xy+y2)=2y-x+y2-4x2-x2+2xy-y2=2y-x-5x2-2xy.