(2x-y)^2(-2x-y)^2-(4x^2+y^2)(4x^2-y^2)
=(2x-y)^2(2x+y)^2-(16x^4-y^4)
=[(2x-y)(2x+y)]^2-16x^4+y^4
=(4x^2-y^2)^2-16x^4+y^4
=16x^4-8x^2y^2+y^4-16x^4+y^4
=-8x^2y^2+2y^4
=-2y^2(4x^2-y^2)
其中x=1/29,y=2/29
=-2*4/29^2*[4/29^2-4/29^2]
=0
=
(2x-y)^2(-2x-y)^2-(4x^2+y^2)(4x^2-y^2)
=(2x-y)^2(2x+y)^2-(16x^4-y^4)
=[(2x-y)(2x+y)]^2-16x^4+y^4
=(4x^2-y^2)^2-16x^4+y^4
=16x^4-8x^2y^2+y^4-16x^4+y^4
=-8x^2y^2+2y^4
=-2y^2(4x^2-y^2)
其中x=1/29,y=2/29
=-2*4/29^2*[4/29^2-4/29^2]
=0
=