Largest subset in which a function is continuous

  • Context: Undergrad 
  • Thread starter Thread starter 0kelvin
  • Start date Start date
  • Tags Tags
    Continuous Function
Click For Summary
SUMMARY

The discussion centers on the continuity of functions, specifically examining the function f(x,y) = x/y, which is continuous everywhere in its domain except where y = 0. It is established that a function can be defined on a domain yet still exhibit points of discontinuity, as illustrated by the piecewise function f(x) = 1 if x = 0 and f(x) = 0 if x ≠ 0, which is not continuous at x = 0 despite being defined for all real numbers. This highlights that continuity is not solely determined by the function's domain.

PREREQUISITES
  • Understanding of function continuity
  • Familiarity with piecewise functions
  • Basic knowledge of real number domains
  • Concept of limits in calculus
NEXT STEPS
  • Study the properties of continuous functions in calculus
  • Explore the concept of limits and their role in determining continuity
  • Examine more complex examples of discontinuous functions
  • Learn about the implications of continuity in real analysis
USEFUL FOR

Students of mathematics, particularly those studying calculus and real analysis, as well as educators seeking to deepen their understanding of function continuity and its exceptions.

0kelvin
Messages
50
Reaction score
5
Take for ex f(x,y) = x/y. Domain is all (x,y) except for y = 0. It's continuous everywhere except for y = 0. Is this always the case? The function is continuous everywhere in its domain?
 
Physics news on Phys.org
0kelvin said:
Take for ex f(x,y) = x/y. Domain is all (x,y) except for y = 0. It's continuous everywhere except for y = 0. Is this always the case? The function is continuous everywhere in its domain?
No. E.g. take ##f(x) = \begin{cases} 1 & \text{ if } x= 0\\ 0 & \text{ if } x\neq 0 \end{cases}##. It's defined for all real numbers, so its domain is ##\mathbb{R}## whereas it is not continuous at ##x=0##. Of course you can easily find more complicated examples.
 

Similar threads

Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 3 ·
Replies
3
Views
4K