MODULE 4

• Logic


  The study of the principles of correct reasoning
• Statement

  A declarative sentence that is either true or false, but not both true and false
• Types of sentences in language

  • Statements
  • Questions
  • Commands
  • Opinions
• Statements

  • They are declarative sentences
  • They are either true or false, but not both true and false
• It may not be necessary to determine whether a sentence is true to determine whether it is a statement
• Sentences that are statements

  • Sorsogon is a province in the Philippines
  • 9 + 2 is a prime number
  • x + 1 = 5
• Sentences that are not statements

  • How are you?
• Simple statement


  A statement that conveys a single idea
• Compound statement


  A statement that conveys two or more ideas
• Logic connectives


  Words or phrases such as and, or, if-then, and if and only if that connect simple statements to create compound statements
• Truth value


  The value of a statement being either true (T) or false (F)
• Truth table


  A table that shows the truth value of a compound statement for all possible truth values of its simple statements
• Negation


  The opposite of a statement, denoted by the tilde symbol (~)