Is a Function Continuous in a Neighborhood If It's Continuous at a Point?

  • Thread starter JG89
  • Start date
  • Tags
    Continuity
In summary, continuity is a concept in mathematics that describes the behavior of a function as it approaches a certain point. It is determined by the existence of a limit at a point and is important in understanding the behavior of functions and solving problems related to them, especially in calculus. There are three types of continuity: point continuity, uniform continuity, and differentiability. Continuity has various real-world applications in fields such as physics, engineering, economics, and biology.
  • #1
JG89
728
1
If f is continuous at x = a, then is it continuous in some neighborhood of x = a as well?
 
Physics news on Phys.org
  • #2
No
A standard example is
f(x)=x x rational
f(x)=0 x irrational

f is continuous at x=0
 
  • #3
lurflurf said:
No
A standard example is
f(x)=x x rational
f(x)=0 x irrational

f is continuous at x=0

And nowhere else. Not even very close to 0.

--Elucidus
 

Related to Is a Function Continuous in a Neighborhood If It's Continuous at a Point?

What is continuity?

Continuity is a concept in mathematics that describes the behavior of a function as it approaches a certain point. A function is considered continuous if there are no sudden jumps or breaks in its graph.

How is continuity determined?

A function is considered continuous if the limit of the function at a point exists and is equal to the value of the function at that point. This means that the function approaches the same value from both the left and right sides of the point.

What is the importance of continuity?

Continuity is an important concept in mathematics because it helps us understand the behavior of functions and allows us to make predictions and solve problems related to them. It is also a fundamental concept in calculus and is used to define derivatives and integrals.

What are the three types of continuity?

The three types of continuity are point continuity, uniform continuity, and differentiability. Point continuity means that a function is continuous at a specific point, while uniform continuity means that a function is continuous over a certain interval. Differentiability means that a function is continuous and has a well-defined derivative at a point.

What are some real-world applications of continuity?

Continuity is used in a wide range of real-world applications, including physics, engineering, economics, and biology. For example, in physics, continuity is used to describe the motion of objects, while in economics, it is used to model the behavior of markets. In biology, continuity is used to study the growth and development of organisms.

Similar threads

  • Calculus
Replies
12
Views
563
Replies
9
Views
1K
Replies
1
Views
2K
  • Calculus
Replies
2
Views
3K
  • Calculus
Replies
1
Views
971
Replies
3
Views
1K
Replies
18
Views
2K
Replies
1
Views
861
Replies
1
Views
1K
Back
Top