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

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

[x^2-y^2(x-4y)(x+4y)-x^2-y^2(x-2y)^2]/[-(2xy)^2][x^2y^2(x-4y)(x+4y)-x^2y^2(x-2y)^2]
[x²y²（x－4y）（x＋4y）－x²y²（x-2y）²]／[-（2xy）²]
＝x²y²（x²-16y²-x²＋4xy－4y²）／-4x²y²
＝20y²-4xy／4
＝5y²-xy

怀疑题目有问题，[x^2-y^2(x-4y)(x+4y)-x^2-y^2(x-2y)^2]化简的话就成[y^2(x-4y)(x+4y)-y^2(x-2y)^2]了
请确认第一项x^2和第三项x^2是否正确

[x^2-y^2(x-4y)(x+4y)-x^2-y^2(x-2y)^2]/[-(2xy)^2]
=[-y^2(x^2-16y^2)-y^2(x^2-4xy+4y^2)]/(-4x^2y^2)
=[-y^2(x^2-16y^2+x^2-4xy+4y^2)]/(-4x^2y^2)
=(2x^2-4xy-12y^2)]/(4x^2)
=(x^2-2xy-6y^2)]/(2x^2)