(3x+1)^2(3x-1)^2 (x-2y)(x+2y)-(x+2y)^2 -36a^2+12ab-b^2 (2m-3

(3x+1)^2(3x-1)^2
=[(3x+1)(3x-1)]^2
=(9x^2-1)^2
=81x^4-18x^2+1
(x-2y)(x+2y)-(x+2y)^2
=(x+2y)(x-2y-x-2y)
=-4y(x+2y)
=-4xy-8y^2
-36a^2+12ab-b^2
=-(36a^2-12ab+b^2)
=-(6a-b)^2
(2m-3n)^2-2m+3n
=(2m-3n)(2m-3n-1)
(x+2y)(x-2y)-(2x-y)(-2x-y)
=x^2-4y^2-4x^2+y^2
=-3x^2-3y^2
(2a+b)^2-(3a-b)^2+5a(a-b)
=4a^2+4ab+b^2-9a^2+6ab-b^2+5a^2-5ab
=5a

因式分解？还是计算？
解1：
(3x+1)^2(3x-1)^2
=[(3x+1)(3x-1)]^2
=(9x^2-1)^2
=81x^4-18x^2+1
解2：
(x-2y)(x+2y)-(x+2y)^2
=(x+2y)(x-2y-x-2y)
=(x+2y)(-4y)
解3：
-36a^2+12ab-b^2