# Study Summary of winter vacation

Source: Internet
Author: User

Mathematical logic: propositional logic basic concept propositional logic equivalence calculus propositional logical reasoning theory first-order logic basic concept first-order logical equivalence calculus and Inference theory

Proposition: A statement that can judge the truth or falsehood. (exclamation, question, qi make a sentence is not a proposition)

Propositions are divided into simple propositions and compound propositions.

Simple proposition symbolization: p,q,r with lowercase english letters, ... Represents a simple proposition. (2) Use "1" to express true, with "0" for false

Negation: No, no, no, no.

Hop ∧: And, at the same time, and, both ... And ..., not only ... And ..., though ... But....

Disjunction ∨: Or, perhaps, possibly.

Implication →: if ... Then ..., if ... So ..., since ... So ..., if ... Just ..., as long as ... It's just that ... Just, ....

Equivalent to ←: When and only if, fully necessary, same, same, ....

A tautology (also known as a perpetual) value is true under various assignments.

Contradictions (also known as the permanent Pseudo-type) under various assignment values are false.

A satisfying formula (not an oxymoron).

Basic equivalents:

Basic tautology Implication type:

Mastered these basic things in the continuous consolidation lay a good foundation.

Study Summary of winter vacation

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