求因式分解题（要越多越好,并请注一下符号的意思）

（x-2y+1)(x+2y-1) (2x-1)(x^2-2x+3) (a-2b+c)^2 因式分解.-4x^2y^3+6x^2y-8xy^2 (2x-y)^2-2(2x-y)+1 (y^4+4y)^2+8(y^2+4y)+16 -4a^2x-8ax+12x^3 4(x+y)^2-12(x+y)+9 (m^2+4m+2)^2 -4 (x+y)^2-4(x+y-1) (x^2-2x-2)(x...