[limit point proof]: L(aub)=l(a)ul(b)

  • Thread starter Thread starter jvt05
  • Start date Start date
  • Tags Tags
    Point Proof
Click For Summary
SUMMARY

The discussion centers on proving the equality of limit points for the union of two sets in R^n, specifically that L(A ∪ B) = L(A) ∪ L(B). Participants emphasize the necessity of demonstrating both inclusions to establish this equality. The proof begins by defining a limit point and analyzing the conditions under which a point x belongs to L(A ∪ B). The conversation highlights the importance of understanding the definitions and properties of limit points in set theory.

PREREQUISITES
  • Understanding of limit points in topology
  • Familiarity with set operations, particularly unions
  • Basic knowledge of real analysis concepts
  • Experience with proofs in mathematical logic
NEXT STEPS
  • Study the definition of limit points in detail
  • Research properties of unions in set theory
  • Explore examples of limit points in R^n
  • Practice proving set equalities using subset arguments
USEFUL FOR

Mathematics students, particularly those studying real analysis or topology, as well as educators looking to enhance their understanding of limit points and set theory proofs.

jvt05
Messages
4
Reaction score
0

Homework Statement


Let L(X) denote the set of limit points of a set X in R^n. How do I prove that L(AUB)=L(A)UL(B)?

The Attempt at a Solution


I know that I have to prove that both sides are subsets of each other, but I have no clue how to start...
 
Last edited:
Physics news on Phys.org
So the standard form of an argument goes like: let x \in L(A \cup B). Then... what does x satisfy (i.e. what is the definition of a limit point of a set X)?
 
Remember that if you want to prove a sets equality, you have to prove both inclusions. En this case, there is a trivial inclusion (which?).
 

Similar threads

Replies
4
Views
1K
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 16 ·
Replies
16
Views
3K
  • · Replies 13 ·
Replies
13
Views
3K
Replies
2
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K