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

第一步:把﹙3x-2y﹚、﹙2x-y﹚各看成一个整体:就是类似于可分别设其为a\b:
﹙3x-2y﹚²-2﹙3x-2y﹚﹙2x-y﹚+﹙2x-y﹚²=[(3x-2y)-(2x-y)]²=(x-y)²

第二步:(x-y)²-6﹙x-y﹚+9=[(x-y)-3]²=(x-y-3)²

望采纳!

题目中 6﹙x-y﹚------应该是-6﹙x+y﹚吧
﹙3x-2y﹚²-2﹙3x-2y﹚﹙2x-y﹚+﹙2x-y﹚²-6﹙x+y﹚+9
=9x²-6xy+4y²-12x²+14xy-4y²+4x²-4xy+y²-6x-6y+9
=x²+4xy+y²-6x-6y+9
=﹙x+y﹚²-6﹙x+y﹚+9
=﹙x+y-3﹚²

=[(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

结果是(x-y-3)^2