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方程2x2+7mx+5m2+1=0的两个实根中一个大于2,另一个小于2,则m的取...
方程2x
2+7mx+5m
2+1=0的两个实根中一个大于2,另一个小于2,则m的取值范围是( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231010862394522/SYS201311012310108623945010_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231010862394522/SYS201311012310108623945010_ST/1.png)
或m>-1
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231010862394522/SYS201311012310108623945010_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101231010862394522/SYS201311012310108623945010_ST/3.png)
或m≥-1
考点分析:
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