若在方程ax2+bx+c=0(a≠0)中,4a+2b+c=0且4a﹣2b+c=0

题型:填空题

问题:

若在方程ax2+bx+c=0(a≠0)中,4a+2b+c=0且4a﹣2b+c=0,则方程的根是(    )。

考点:一元二次方程的解法
题型:填空题

补出下列名句名篇中的空缺部分

1.大漠孤烟直,_________________。(王维《使至塞上》)

 

 2.我劝天公重抖擞,_________________。(龚自珍《己亥杂诗》)

  3.忽如一夜春风来,_________________。(岑参《白雪歌送武判官归京》)

  4.日出江花红胜火,_________________。(白居易《忆江南》)

题型:填空题

供应胃底的血管起自()

A.腹腔动脉

B.肝总动脉

C.脾动脉

D.胃网膜右动脉

E.肝固有动脉

题型:填空题

Passage 1In order to produce goods and services, businesses need to buy the required raw materials and equipment. Many firms need to order components or equipment to their own specifications which will later be used to produce a finished product. Firms need reliable suppliers who must be:Stable. Firms that can not supply goods in time to the purchasing company may mean delays and holdups for customers. Thus the purchasing company should check the financial background of its suppliers.Able. The purchasing company must investigate whether potential suppliers are able to make the goods required. This may mean looking at the firm’s equipment and staff expertise if a large or important order is being considered. Some purchasing departments may ask for evidence of the firm having done similar work for other organizations before placing an order. Trade directories and specialist magazines are a useful starting point in this research.Clear. What is required will usually be made clear in a specification. The specification or “spec” will give the exact technical details of what is needed in terms of size, shape, color and performance of the items to be purchased. The supplying firm must then meet this specification exactly.An important problem all purchasing companies have to deal with is whether to use one or two or several suppliers. By using several suppliers it is argued that competition between them will force prices down. And delays or disruption at one supplier will not affect too much. Arguments against this are that researching various suppliers is time-consuming and expensive, and low prices might mean reduced quality. Using fewer suppliers for larger orders can mean that the purchaser receives greater attention and discount for bulk purchases. The suppliers will be more involved in the firm’s business, too.

A “clear” supplying firm must initially give the purchaser its specifications clearly and in exact technical detail. ( )

题型:填空题

下列关于水系统回水温度一致性的合格指标描述正确的是()

A、检测持续时间内,冷水系统各一级支管路回水温度间的允许偏差为1°C;热水系统各一级支管路回水温度间的允许偏差为1°C

B、检测持续时间内,冷水系统各一级支管路回水温度间的允许偏差为2°C;热水系统各一级支管路回水温度间的允许偏差为2°C

C、检测持续时间内,冷水系统各一级支管路回水温度间的允许偏差为1°C;热水系统各一级支管路回水温度间的允许偏差为2°C

D、检测持续时间内,冷水系统各一级支管路回水温度间的允许偏差为2°C;热水系统各一级支管路回水温度间的允许偏差为1°C

题型:填空题

亲合起源于( )。

A.本能
B.依恋
C.学习
D.社会性

更多题库