Proving f(z) is a continuous function in the entire complex plane

Click For Summary

Homework Help Overview

The discussion revolves around proving the continuity of the function f(z) = Re(z) + Im(z) in the entire complex plane, focusing on the properties of the real and imaginary components of complex numbers.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss the need to demonstrate the continuity of Re(z) and Im(z) separately, with some suggesting to express z in terms of its real and imaginary parts.

Discussion Status

There are various lines of reasoning being explored, including the application of the definition of continuity and the examination of the continuity of the individual components of the function. Some participants are questioning the continuity of Re(z) and Im(z) directly.

Contextual Notes

Participants are considering the definitions and properties of continuity, as well as the implications of the function's behavior across its entire domain.

lonewolf999
Messages
3
Reaction score
0

Homework Statement


Show that the function f(z) = Re(z) + Im(z) is continuous in the entire complex
plane.


Homework Equations





The Attempt at a Solution



I know that to prove f(z) is a continuous function i have to show that it is continuous at each part of its domain.

I take it that means i have to prove that Re(z) and Im(z) are continuous, however i have tried reading through my notes on how to do this and havn't been able to come up with a starting point.
 
Physics news on Phys.org
Try writing out z as the usual combination of x + iy. Then what is Re(z) and Im(z)? Are these functions continuous?
 
if i take z=x+iy, then Re(z)=x and Im(z)=y, however i can't finish it there.
 
Is the function f(z) = x continuous? Is the function f(z) = y continuous? Start with the definition of continuity.
 
Is it by some chance true that [tex]|Re(z)|\leq |z|[/tex]?
 

Similar threads

Replies
7
Views
3K
  • · Replies 27 ·
Replies
27
Views
2K
  • · Replies 17 ·
Replies
17
Views
4K
Replies
8
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
8
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
1K