问题 解答题 已知x-3y=0,求(2x+y)(x-y)x2-2xy+y2的值. 答案 ∵x-3y=0,∴x=3y,∴原式=(2x+y)(x-y)(x-y)2=2x+yx-y=6y+y3y-y=72.故答案为72.