如果方程ax2+2x+1=0有两个不等实数根,则实数a的取值范围是( )。

题型:填空题

问题:

如果方程ax2+2x+1=0有两个不等实数根,则实数a的取值范围是(    )。

考点:一元二次方程的解法
题型:填空题

根据短文内容, 从短文后的选项中选出能填入空白处的最佳选项。 选项中有两项为多余选项。

     1_____ People use money to buy food, furniture, books, bicycles and hundreds of other things they need

or want. When they work, they usually get paid in money.

     Most of the money today is made of metal or paper. 2_____ One of the first kinds of money was shells.

     Shells were not the only things used as money. In China, cloth and knives were used. In the Philippine

Islands, rice was used as money for a long time. Elephant tusks, monkey tails and salt were used as money

in parts of Africa.

     The first metal coins were made in China. They were round and had a square hole in the centre. 3_____. 

     Different countries have used different metals and designs for their money. 4_____ Sweden and Russia

used copper to make their money. Later some countries began to make coins of gold and silver.

     But even gold and silver were inconvenient if you had to buy something expensive. Again the Chinese

thought of a way to improve money. 5_____ The first paper money looked more like a note from one person

to another than the paper money used today.

     Money has had an interesting history from the days of shell money until today.

A. The first coins in England were made of tin (锡).

B. But people used to use all kinds of things as money.

C. No one knows for certain when people began to use money.

D. People strung (串连) them together and carried them from place to place.

E. Money, as we know, is all made of paper.

F. They began to use paper money.

G. Today anyone will accept money in exchange for goods and services.

题型:填空题

以下有关BNMS系统账户对机制的描述正确的包括()。

A.通过设置集团内两两账户之间的关系,实现集团账户间资金划拨、统一支付、累计积数等功能

B.在期货出/入金、主动收款下设置账户对机制,可对资金汇划的方向进行更严格的管理

C.针对账户对,可通过设置额度进行交易控制

D.针对账户对,可通过设置单笔和每日限额进行交易控制

题型:填空题

4台Linux主机通过图6-1所示的方式互联,则实现PC1与PC4之间互访的步骤为:

1.运行 (3) 命令关闭计算机,在PC2与PC3上添加第二块网卡(eth1),重新启动;

2.在PC2与PC3上为第二块网卡分配IP地址,并激活该网络接口,对于PC3,应执行 (4)

3.如果使用routed作为路由器进程,则作为路由器的PC2与PC3仅支持路由协议 (5) ;如果在PC2与PC3上设置静态路由信息并开启路由功能,对于PC2则应执行 (6)

4.在PCI和PC4上配置各自的默认同关,对于PC1,应执行 (7)

(6)处填()

A.route add-net 202.114.100.0/24 gw 10.1.1.1

B.route add-net 202.114.100.0/24 gw 10.1.1.2

C.route add-net 202.1 14.100.0/24 gw 10.1.1.2 echo"1">/proc/sys/net/ipv4/ip forward

D.route add-net 202.114.110.0/24 gw 10.1.1.1 echo"1">/proc/sys/net/ipv4/ip forward

题型:填空题

10kV开关测绝缘前不需确认的()。

A.开关在试验位置

B.开关二次插头连接位

C.开关分闸

D.出线电缆无压

题型:填空题

营养不良患儿最先减少皮下脂肪的部位是

A.面部
B.躯干
C.四肢
D.腹部
E.臀部

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