MHB Identity Proof: (A-B)-C=A-(B∪C)

Click For Summary
To prove the identity (A-B)-C=A-(B∪C), the discussion highlights the use of set identities, specifically A-B=A\bar{B} and \overline{B∪C}=\bar{B}\bar{C}. The proof involves manipulating these identities to show the equivalence. The conversation emphasizes the importance of understanding set operations and their properties, including commutativity and associativity. Participants are encouraged to apply the provided identities to validate the equality. This exploration of set theory identities is crucial for grasping advanced concepts in mathematics.
gicm
Messages
1
Reaction score
0
Show that(A-B)-C=A-(BUC)
 
Physics news on Phys.org
This can be shown using identities on sets. Two identities are: $A-B=A\bar{B}$ and $\overline{B\cup C}=\bar{B}\bar{C}$. Here $\bar{A}$ denotes the complement of $A$, and I skip intersection, i.e., I write $AB$ for $A\cap B$. There are numerous other identities on sets, such as commutativity and associativity of intersection and union, laws involving the empty set and so on. Can you use the ones I provided to prove your equality?
 
First trick I learned this one a long time ago and have used it to entertain and amuse young kids. Ask your friend to write down a three-digit number without showing it to you. Then ask him or her to rearrange the digits to form a new three-digit number. After that, write whichever is the larger number above the other number, and then subtract the smaller from the larger, making sure that you don't see any of the numbers. Then ask the young "victim" to tell you any two of the digits of the...

Similar threads

  • · Replies 5 ·
Replies
5
Views
5K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 18 ·
Replies
18
Views
3K
  • · Replies 0 ·
Replies
0
Views
2K
  • · Replies 3 ·
Replies
3
Views
129K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 21 ·
Replies
21
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K