满分5 >
初中数学试题 >
5月23日8时40分,哈尔滨铁路局一列满载着2400吨“爱心”大米的专列向四川灾...
5月23日8时40分,哈尔滨铁路局一列满载着2400吨“爱心”大米的专列向四川灾区进发,途中除3次因更换车头等原因必须停车外,一路快速行驶,经过80小时到达成都.描述上述过程的大致图象是( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573018_ST/images0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573018_ST/images1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573018_ST/images2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573018_ST/images3.png)
考点分析:
相关试题推荐
如果关于x的一元二次方程k
2x
2-(2k+1)x+1=0有两个不相等的实数根,那么k的取值范围是( )
A.k>
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573017_ST/0.png)
B.k>
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573017_ST/1.png)
且k≠0
C.k<
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573017_ST/2.png)
D.k≥
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573017_ST/3.png)
且k≠0
查看答案
下列计算中,正确的是( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573016_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573016_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573016_ST/2.png)
D.
查看答案
已知点P是半径为5的圆O内一定点,且OP=4,则过点P的所有弦中,弦长可能取到的整数值为( )
A.5,4,3
B.10,9,8,7,6,5,4,3
C.10,9,8,7,6
D.12,11,10,9,8,7,6
查看答案
下列二次根式:
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573014_ST/0.png)
、
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573014_ST/1.png)
、
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573014_ST/2.png)
、
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573014_ST/3.png)
中与
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573014_ST/4.png)
是同类二次根式的个数为( )
A.1个
B.2个
C.3个
D.4个
查看答案
样本方差的计算式S
2=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000613935957351/SYS201311030006139359573013_ST/0.png)
[(x
1-30)
2+(x
2-30)
2+…+(x
20-30)
2]中,数字20和30分别是( )
A.众数、中位数
B.方差、标准差
C.样本中的数据的个数、中位数
D.样本中数据的个数、平均数
查看答案