分解因式﹙3x-2y﹚²-2﹙3x-2y﹚﹙2x-y﹚+﹙2x-y﹚²-6﹙x-y﹚+9

问题描述:

分解因式﹙3x-2y﹚²-2﹙3x-2y﹚﹙2x-y﹚+﹙2x-y﹚²-6﹙x-y﹚+9

=[(3x-2y)²-2(3x-2y)(2x-y)+(2x-y)²]-6(x-y)+9
=[(3x-2y)-(2x-y)]²-6(x-y)+9
=(x-y)²-6(x-y)+9
=[(x-y)-3]²
=(x-y-3)²