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Bridge course
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Countable and uncountable sets
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Proof techniques
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Example of a nonconstructive proof
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Direct proof
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Disproof by counterexample
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Proof by cases
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Proving properties of absolute value
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Proof by contrapositive
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Proof by contradiction
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Challenge
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Proof by induction
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Proof by strong induction
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Proving de Moivre's theorem
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Visual proof
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Challenge
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Relations
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Equivalence relations
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Intersection of equivalence relations
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Representing relations using matrices
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Combining relations
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Composition of relations
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Inverse of composite relation
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Representing relations using digraphs
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Properties of relations
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Proving equivalence relations
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What is a relation?
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Finding the inverse of a relation on a finite set
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Functions (bridge course)
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Injective, surjective, and bijective
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Intro
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Is it bijective? (infinite domain)
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Is it injective?
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Is it surjective?
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Proof: Composite of surjections is surjection
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Proving properties of injective, surjective, and bijective functions
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Bridge course
›
Functions (bridge course)
›
Injective, surjective, and bijective
›
Is it surjective?
Proof: Composite of surjections is surjection
YouTube videos
45594
The Composition of Surjective(Onto) Functions is Surjective Proof
The Math Sorcerer