作业帮 > 数学 > 作业

【初二数学】当x取何整数时,分式(x+1/(x-1)-x²+1/x²-2x+1)÷1/x-1的结果为

来源:学生作业帮 编辑:神马作文网作业帮 分类:数学作业 时间:2024/11/10 16:11:30
【初二数学】当x取何整数时,分式(x+1/(x-1)-x²+1/x²-2x+1)÷1/x-1的结果为负整数.
【初二数学】当x取何整数时,分式(x+1/(x-1)-x²+1/x²-2x+1)÷1/x-1的结果为
[(x+1)/(x-1)-(x²+1)/(x²-2x+1)]÷1/(x-1)
=[(x+1)(x-1)/(x-1)²-(x²+1)/(x-1)²]×(x-1)
=[(x²-1)/(x-1)²-(x²+1)/(x-1)²]×(x-1)
=[(x²-1-x²-1)/(x-1)²]×(x-1)
=[-2/(x-1)²]×(x-1)
=-2/(x-1)
结果是负整数,那么x-1是2的正因数,即1或2
当x-1=1,即x=2时,原式=-2;
当x-1=2,即x=3时,原式=-1
所以x=2,或3