Logic
Logical Operations and Truth Tables
Keywords: logic, true, false, negation, disjunction, conjunction, implication, equality
A mathematical sentence is a sentence that states a fact or contains a complete idea. A sentence that can be judged to be true or false is called a statement.
The statement can be true (T) or false (⊥).
P, Q, R,... statements
Example:
This girl is beatiful.  not a statement.
Today is Wensday.  statement.
Negation (¬) (not)
P

¬P

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Disjunction (∨) (or)
P

Q

P∨Q

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Conjunction (∧) (and)
P

Q

P∧Q

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Implication (⇒) (if ..., than...)
P

Q

P⇒Q

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Equality (⇔) (biconditional)
P

Q

P⇔Q

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