Stage 37 · Beyond (Optional)

37.4.2 Universal and Existential Quantifiers

37.4 Mathematical Proof and Logic: Induction, Contradiction, and Construction

Point 2 of 5

37.4.2 Universal and Existential Quantifiers

Core idea

"For all" is written ∀ and "there exists" is written ∃, and negating a statement swaps the two and flips what follows.

Module goal. Make the why behind a result clear, master the language of mathematical statements and the three main styles of proof, and move from being able to compute to being able to prove.
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