问题 填空题
已知点P(m,n)是直线x+y+2=0上任意一点,则z=
(m-1)2+(n+1)2
的最小值是______
答案

要求z=

(m-1)2+(n+1)2
的最小值,就是求点P到(1,-1)的距离的最小值,因为点P(m,n)是直线x+y+2=0上任意一点,因而只须求(1,-1)到直线x+y+2=0的距离,就是求Z的最小值,即
|1-1+2|
2
=
2

故答案为:

2

单项选择题

Information systems design is defined as those tasks that focus on the specification of a detailed computer-based solution. Typically, there are four systems design tasks for in-house development.

1) The first task is to specify(),which defines the technologies to be used by one, more, or all information systems in terms of their data, processes, interfaces, and network components. This task is accomplished by analyzing the data models and process models that are initially created during requirements analys16.

2) The next systems design task is to develop the (). The purpose of this task is to prepare technical design specifications for a database that will be adaptable to future requirements and expansion.

3) Once the database prototype has been built, the systems designer can work closely with system users to develop input, output and dialogue specifications. The()must be specified to ensure that the outputs are not lost, misrouted, misused, or incomplete.

4) The fourth design task involves packaging all the specifications from the previous design tasks into a set of specifications that will guide the() activities during the following phases of the systems development methodology.

Finally, we should() and update the project plan accordingly. The key deliverable should include a detailed plan for the construction phase that should follow

The()must be specified to ensure that the outputs are not lost, misrouted, misused, or incomplete.

A.format and layout

B.transaction details

C.additional instructions

D.internal controls

问答题