因式分解.1.(x²-2x)²-2x²+4x-3 (x²-2x)²-2x²+4x-3 2. (m+2n)²-(m+2n)-12 3. 2（x-y）²z²-4（x-y）z²-48z²y²-xy-12x²

因式分解.1.(x²-2x)²-2x²+4x-3 (x²-2x)²-2x²+4x-3 2. (m+2n)²-(m+2n)-12 3. 2（x-y）²z²-4（x-y）z²-48z²y²-xy-12x²
因式分解.1.(x²-2x)²-2x²+4x-3
       (x²-2x)²-2x²+4x-3
   2.        (m+2n)²-(m+2n)-12
   3.        2（x-y）²z²-4（x-y）z²-48z²
y²-xy-12x²

因式分解.1.(x²-2x)²-2x²+4x-3 (x²-2x)²-2x²+4x-3 2. (m+2n)²-(m+2n)-12 3. 2（x-y）²z²-4（x-y）z²-48z²y²-xy-12x²
(x²-2x)²-2x²+4x-3
= (x²-2x)²-2(x²-2x)-3
= (x²-2x-3)(x²-2x+1)
=(x+1)(x-3)(x-1)²
(m+2n)²-(m+2n)-12
=(m+2n-4)(m+2n+3)
2（x-y）²z²-4（x-y）z²-48z²
=2z²[(x-y）²-2（x-y）-24]
=2z²(x-y-6）（x-y+4）
y²-xy-12x²
=(y-4x)(y+3x)