中二 因式分解(急!!!20點)

4 a ^ 3 - ( b ^ 2 - 6 b + 9 ) a
a(4a^2-(b-3)^2)
a(2a-b+3)(2a+b-3)
__________________
x ^ 2 - 1 2 x y + 3 6 y ^ 2 - x + 6 y
(x ^ 2 - 1 2 x y + 3 6 y ^ 2) - (x - 6 y)
(x-6y)^2-(x-6y)
(x-6y)(x-6y-1)
____________________
1- x ^ 2 + 4 x y - 4 y ^ 2
1-(x^2-4xy+4y^2)
1-(x-2y)^2
(1-x+2y)(1+x-2y)
_______________________
x ^ 6 + 2 x ^ 4 y ^ 2 + y ^ 4 x ^2 - 4
x^2(x^4+2x^2y^2+y^2)-4
(x^2+y^2)x^2-4
(x^3+y^3)^2-4
(x^3+y^3-4)(x^3+y^3+4)
__________________________
8 c ^ 2 - 4 c + 4 c d - 2 d
2(4c^2-2c+2cd-d)
2(2c(2c-1)+d(2c-1))
2(2c+d)(2c-1)
____________________

2010-09-21 23:09:02 補充：
p d s - 3 a t - p q t +3 a s
(pds-pqt)-(3at-3as)
p(ds-qt)-3a(t-s)

2010-09-21 23:11:40 補充：
.- 2 a ^ 4 b ^ 4 + 3 2 c ^ 4
-2(a^4b^4-16c^4)
-2(a^2b^2-4c^2)(a^2b^2+4c^2)
-2(ab-2c)(ab+2c)(a^2b^2+4c^2)

圖片參考：http://img202.imageshack.us/img202/8420/screenhunter01sep212312.gif


http://img202.imageshack.us/img202/8420/screenhunter01sep212312.gif