A Proposition is a sentence that is either true or false, but not both. Propositions are also known as statements.
Truth value is either true or false
When a proposition is formed by combining two propositions with the word and, it is called a conjunction, and the two propositions are called conjuncts. A conjunction is true if both of its conjuncts are true and false otherwise.
When a proposition is formed by combining two propositions with the word or, it is called a disjunction, and the two propositions are called disjuncts. A disjunction is true if at least one of its disjuncts is true and false otherwise.
And & or are both connectives, both require two propositions
A negation of a proposition is a statement that has the opposite meaning of the original proposition. Therefore, the truth value of a negation is the opposite of the original proposition’s truth value.
Not is a connective, only requires one proposition
A proposition of the form if hypothesis, then conclusion is called a conditional. It is also know as an implication or an if-then statement.
If-then is a connective
A conditional is true if the conclusion is true, and false if the conclusion is false, but if the hypothesis is false, then the conditional is true
if hypothesis, then conclusion if not conclusion, then not hypothesis Writing the contrapositive.
A conditional and its contrapositive are true at the same times
if hypothesis, then conclusion if conclusion, then hypothesis Writing the converse.
The converse may have a different truth value than the original conditional