初二数学下册人教版三新练习册P3.12题的最后一题不明白,原题是这样的:通分:1/x2-1与2x/x2-3x+2

问题描述:

初二数学下册人教版三新练习册P3.12题的最后一题不明白,原题是这样的:通分:1/x2-1与2x/x2-3x+2

通分1/X2-1与2X/X2-3X+2
1/X2-1
=1/(X-1)(X+1)
=(X-2)/(X-1)(X+1)(X-2)
2X/X2-3X+2
=2X/(X-2)(X-1)
=2X(X+1)/(X-2)(X-1)(X+1)