满分5 >
初中数学试题 >
方程x2-5x-6=0的两根之和为( ) A.-6 B.5 C.-5 D.1
方程x2-5x-6=0的两根之和为( )
A.-6
B.5
C.-5
D.1
考点分析:
相关试题推荐
在一个口袋中有3个完全相同的小球,把它们分别标号为1,2,3,随机地摸取一个小球然后放回,再随机地摸出一个小球.则两次取的小球的标号相同的概率为( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078004_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078004_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078004_ST/2.png)
D.
查看答案
某校九个班进行迎新春大合唱比赛,用抽签的方式确定出场顺序.签筒中有9根形状、大小完全相同的纸签,上面分别标有出场的序号1,2,3,…,9.下列事件中是必然事件的是( )
A.某班抽到的序号小于6
B.某班抽到的序号为0
C.某班抽到的序号为7
D.某班抽到的序号大于0
查看答案
在一元二次方程x
2-4x-1=0中,二次项系数和一次项系数分别是( )
A.1,4
B.1,-4
C.1,-1
D.x
2,4
查看答案
下列计算:①
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078001_ST/0.png)
=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078001_ST/1.png)
;②
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078001_ST/2.png)
;③
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078001_ST/3.png)
=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078001_ST/4.png)
;④
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078001_ST/5.png)
=4.其中错误的是( )
A.①
B.②
C.③
D.④
查看答案
要使式子
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078000_ST/0.png)
在实数范围内有意义,字母a的取值必须满足( )
A.a≥0
B.a≥-
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078000_ST/1.png)
C.a≠-
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000722062107846/SYS201311030007220621078000_ST/2.png)
D.a≤-
查看答案