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Discrete Mathematics I β€” Logic, Proof, and Structure

The language mathematics is actually written in: propositions, quantifiers, and proof, then the sets, functions, relations, graphs, and counting arguments that every algorithm and probability model is built out of.

Free to read now, no account needed: Readiness: reading mathematics precisely. Create a free account to open the other chapters, take the quizzes and keep your progress.

1 Introduction to discrete mathematics πŸ”’

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  • Discrete versus continuous ~8 min
  • Objects, collections, and structures ~8 min
  • The language of mathematical notation ~8 min
  • Counting as a first discrete question ~8 min
  • Discrete structures in computer science ~8 min
  • Finite, infinite, and a first look at countability ~8 min
  • Definition, theorem, proof: how this course is built ~8 min

2 Logic and propositions πŸ”’

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  • Propositions and truth values ~8 min
  • Negation, conjunction, and disjunction ~10 min
  • Truth tables ~10 min
  • Exclusive or and other connectives ~8 min
  • The conditional statement ~10 min
  • Converse, inverse, and contrapositive ~10 min
  • The biconditional ~8 min
  • Tautologies, contradictions, and contingencies ~8 min
  • Logical equivalence ~9 min
  • De Morgan's laws ~9 min
  • Necessary and sufficient conditions ~9 min
  • Translating English into symbolic logic ~10 min
  • Valid arguments and rules of inference ~10 min

3 Predicate logic πŸ”’

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  • Predicates and truth sets ~8 min
  • The universal quantifier ~9 min
  • The existential quantifier ~8 min
  • Why the domain of discourse matters ~8 min
  • Negating quantified statements ~9 min
  • Nested quantifiers ~9 min
  • Order of quantifiers changes meaning ~9 min
  • Translating English into predicate logic ~9 min
  • Logic in programming and databases ~8 min

4 Methods of proof πŸ”’

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  • What a proof must do ~9 min
  • Definitions are the raw material ~8 min
  • Direct proof ~10 min
  • Proof by contrapositive ~9 min
  • Proof by contradiction ~10 min
  • Proof by cases ~8 min
  • Counterexamples and disproof ~8 min
  • Existence proofs ~8 min
  • Uniqueness proofs ~8 min
  • Constructive versus nonconstructive ~8 min
  • Choosing a proof strategy ~9 min
  • Common proof errors ~9 min

5 Mathematical induction πŸ”’

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  • The principle of mathematical induction ~9 min
  • Anatomy of an induction proof ~8 min
  • Induction and summation formulas ~9 min
  • Induction with inequalities ~8 min
  • Induction with divisibility ~8 min
  • Induction on recursively defined objects ~8 min
  • Strong induction ~9 min
  • When strong induction is needed ~8 min
  • The well-ordering principle ~8 min
  • Induction, recursion, and algorithms ~8 min

6 Set theory πŸ”’

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  • Sets, elements, and set-builder notation ~11 min
  • Subsets and proper subsets ~10 min
  • Set equality and double inclusion ~9 min
  • Union, intersection, difference ~11 min
  • Complement and the universal set ~9 min
  • Venn diagrams ~10 min
  • Set identities ~11 min
  • Proving set identities two ways ~11 min
  • Cartesian products ~9 min
  • Power sets ~9 min
  • Cardinality of finite sets ~10 min
  • Infinite sets and countability ~12 min

7 Functions πŸ”’

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  • Functions between sets ~12 min
  • Domain, codomain, range, image ~12 min
  • One-to-one functions ~12 min
  • Onto functions ~12 min
  • Bijections ~12 min
  • Function composition ~14 min
  • Inverse functions ~14 min
  • Floor and ceiling ~12 min
  • Images and preimages of sets ~14 min
  • Growth of functions: a first look ~12 min

8 Relations πŸ”’

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  • Binary relations ~9 min
  • Representing relations: matrices and digraphs ~8 min
  • Reflexive and irreflexive ~8 min
  • Symmetric and antisymmetric ~8 min
  • Transitive relations ~8 min
  • Combining and composing relations ~9 min
  • Equivalence relations ~8 min
  • Equivalence classes ~8 min
  • Partitions ~8 min
  • Partial orders ~8 min
  • Hasse diagrams ~9 min

9 Sequences and recurrence πŸ”’

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  • Sequences and general terms ~9 min
  • Arithmetic and geometric sequences, discretely ~9 min
  • Recursive definitions ~9 min
  • Recursively defined sets and structures ~9 min
  • Recurrence relations ~9 min
  • Solving by iteration ~9 min
  • Linear homogeneous recurrences ~10 min
  • The Fibonacci recurrence ~10 min
  • Recursion in algorithms ~9 min

10 Counting principles πŸ”’

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  • The product rule ~9 min
  • The sum rule ~8 min
  • Counting with the complement ~8 min
  • Factorials ~7 min
  • Permutations ~9 min
  • Combinations ~9 min
  • Permutations versus combinations ~8 min
  • Binomial coefficients and Pascal's triangle ~9 min
  • The binomial theorem, counted ~9 min
  • Counting with restrictions ~10 min
  • Combinatorial proof ~9 min
  • The pigeonhole principle ~9 min

11 Introduction to graph theory πŸ”’

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  • What a graph is ~8 min
  • Simple graphs, multigraphs, loops ~8 min
  • Directed graphs ~8 min
  • Graph terminology and special graphs ~9 min
  • Degree of a vertex ~8 min
  • The handshaking theorem ~9 min
  • Walks, paths, and trails ~9 min
  • Cycles ~8 min
  • Connectedness and components ~8 min
  • Subgraphs ~8 min
  • Graph isomorphism ~9 min

12 Trees πŸ”’

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  • What a tree is ~9 min
  • Properties of trees ~9 min
  • Rooted trees ~9 min
  • Binary trees ~9 min
  • Tree traversal ~10 min
  • Binary search trees ~10 min
  • Spanning trees ~10 min
  • Counting with trees ~9 min
  • Trees in algorithms and data structures ~9 min

13 Introduction to algorithms πŸ”’

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  • What an algorithm is ~12 min
  • Reading and writing pseudocode ~13 min
  • Correctness and termination ~13 min
  • Loop invariants ~14 min
  • Proving an algorithm correct ~15 min
  • Linear search ~12 min
  • Binary search ~14 min
  • Bubble and insertion sort ~15 min
  • Recursive algorithms ~13 min
  • Recursion versus iteration ~12 min

14 Asymptotic analysis πŸ”’

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  • Counting operations ~9 min
  • Growth rates ~9 min
  • Big-O ~10 min
  • Proving a Big-O bound ~10 min
  • Big-Omega ~9 min
  • Big-Theta ~9 min
  • Common complexity classes ~9 min
  • Polynomial versus exponential ~9 min
  • Comparing algorithms ~10 min

15 Discrete probability fundamentals πŸ”’

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  • Sample spaces and events ~12 min
  • Counting-based probability ~12 min
  • Probability rules ~12 min
  • Complementary and inclusive-or events ~12 min
  • Conditional probability, revisited ~14 min
  • Independence ~12 min
  • Bayes' theorem, revisited ~14 min
  • Random variables ~12 min
  • Expected value, revisited ~12 min
  • Linearity of expectation ~12 min