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3: Functions

  • Page ID
    88851
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    • 3.1: Functions
      This page explains essential concepts of mathematical mapping, particularly focusing on functions, including definitions of key terms like function, surjective, injective, bijection, and inverse mapping. It emphasizes that a function maps each input to one output, and onto functions connect all codomain elements. The existence of inverse mappings depends on the one-to-one property of functions.
    • 3.2: Boolean Algebra
      This page explores the connection between arithmetic operations and Boolean algebra, detailing terminology and definitions relevant to Boolean functions. It highlights methods for representing and simplifying these functions through algebraic techniques. The text includes practical exercises for evaluating and designing Boolean functions and their circuit representations, aiming to demonstrate the optimization of logical expressions for various applications.
    • 3.3: Modulo Arithmetic
      This page covers modulo arithmetic, defining how integers are equivalent mod n to their remainders and highlighting the significance of order of operations. It includes examples, checkpoints, exercises for practice—such as function evaluations and solving equations—and presents theorems and lemmas on divisibility and equivalence with proofs.
    • 3.4: Combinatorics- Second Counts
      This page covers permutations and combinations, defining them as arrangements with order sensitivity and selections without, respectively. It uses the alphabet characters {a, b, c} for examples and poses checkpoints for practice in calculating these concepts across various scenarios.
    • 3.5: Proof by Contradiction
      This page discusses direct proof and proof by contradiction, featuring a theorem that the composition of two functions is a function. The proof is divided into two parts: confirming that every domain element maps to a codomain element, and using contradiction to establish uniqueness in mapping. It also introduces mapping composition and explains its operation with two mappings.


    This page titled 3: Functions 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.