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4: Relations

  • Page ID
    88859
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    • 4.1: Example- Error Correcting Codes
      This page outlines data encoding for transmission, emphasizing error detection and correction due to potential noise interference. It introduces the concept of distance between binary strings to differentiate messages and suggests considerations for designing error-correcting codes to manage single-bit errors.
    • 4.2: Mathematical Relations
      This page discusses the concept of relations in data organization, defining them as subsets of a Cartesian product. It covers various types of relations—reflexive, symmetric, anti-symmetric, and transitive—illustrated with examples involving integers and real numbers. The text highlights specific properties and contexts, such as subset inclusion, divisibility, and the less than or equal to relation.
    • 4.3: Equivalence Relations
      This page explores equivalence relations in mathematics, detailing properties like reflexivity, symmetry, and transitivity. It defines equivalence classes and provides checkpoints for assessing equivalence in subsets, modular arithmetic, and integer divisibility.
    • 4.4: Partially Ordered Sets
      This page defines partially ordered sets (posets) and their properties like reflexivity, anti-symmetry, and transitivity. It explains representation through Hasse diagrams and illustrates examples such as numeric divisibility and subset relations. Key terms related to posets, including comparable elements, total ordering, and lattices, are defined, alongside practical checkpoints for assessing poset properties and constructing Hasse diagrams.
    • 4.5: Combinatorics- Inclusion/Exclusion
      This page explains the inclusion-exclusion principle for counting distinct elements in overlapping sets, detailing how to adjust for over-counting overlaps. An example with students in math courses illustrates this principle. It also defines a derangement as a permutation where no element retains its original position, and concludes with practice checkpoints on related counting problems.


    This page titled 4: Relations is shared under a GNU Free Documentation License 1.3 license and was authored, remixed, and/or curated by Mark A. Fitch via source content that was edited to the style and standards of the LibreTexts platform.