What are the eight commonly used symbolic representations of intervals and the number line represent

The closed interval [a,b] indicates the inequality.

a x b, half-open and semi-closed interval [a, b], denotes inequality a x b, a, b], denotes inequality a x b, open interval.

a,b), denotes inequality a x b,a,+ infinity), denotes inequality x a,-,infinity,a), denotes inequality x a,a,+ infinity), denotes inequality x a,-infinity, a], denotes inequality x a, number axis.

on, with an equal sign to draw a solid point, without an equal sign to draw a blank circle,

An interval is a set of all the real numbers between two particular real numbers, and possibly both.

Interval notation is the way in which a variable is represented within a certain interval. In the common interval notation, parentheses indicate "exclude" and square brackets indicate "include".

For example, the interval (10,20) represents all real numbers between 10 and 20, but does not include 10 or 20On the other hand, [10,20] denotes all real numbers between 10 and 20, as well as 10 and 20

The intervals of r are as follows (a and b are real numbers and a < b):

1.(a,b) =

2.[a,b] =

3.[a,b) =

4.(a,b] =

5.(a,∞)=

6.[a,∞)=

7.(-b) =

8.(-b] =

9.(-= r itself, the set of real numbers.)

11.Null set.

1, 5, 7, 9, and 11 are called "open intervals" (because they are open sets), and 2, 6, 8, 9, 10, and 11 are called "closed intervals" (because they are closed sets).3 and 4 are sometimes referred to as "half-open intervals" or "semi-closed intervals".9 and 11 are "open" and "closed" at the same time, not "half-open" or "half-closed".

1, 2, 3, 4, 10 and 11 bounded intervals; 5, 6, 7, 8 and 9 are unbounded intervals. 10 is a single point.

The open interval (a, b) refers to a x b

The closed interval [a,b] refers to a x b

x is less than 4, and x is not equal to 0, and x is not equal to -4, look.

The intervals are expressed in the following ways: (a, b) (b a), (open interval); (a,b](b a), (half-open and half-closed interval); (a,b](b a), (half-open and half-closed interval); [a,b](b a), (closed interval).

In mathematics, an interval usually refers to a set of real numbers such that if x and y are two numbers in a set, then any number between x and y also belongs to that set.

For example, a set of real numbers that conform to 0 x 1 is an interval that contains , and all real numbers between 0 and 1. Other examples include: sets of real numbers, sets of negative real numbers, etc.

2 "Limb Belt X<0

x|=-xf(x)=1+(-x-x)/2=1-x0<=x<=2

x|=xf(x)=1+(x-x)/2=1

So the history of the reed.

f(x)=1-x,(-21,(0<=x《Judgment = 2)