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MA 110: Finite Math Dr. Maria Byrne Instructional Laboratory 0345. Lecture 1/16/2009 Venn Diagrams Homework: 1.1: 5, 9-15, 21-22; (56 for a BP) Due next Wednesday 1/21 . Today we will:. Take MA110 pre-test. Consider the validity of a couple arguments.
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MA 110: Finite MathDr. Maria ByrneInstructional Laboratory 0345 Lecture 1/16/2009 Venn Diagrams Homework: 1.1: 5, 9-15, 21-22; (56 for a BP) Due next Wednesday 1/21
Today we will: • Take MA110 pre-test. • Consider the validity of a couple arguments. • Learn about Venn diagrams, which can be used to determine validity, by completing the Venn Diagram worksheet.
Recall: • Syllogism • Basis of deductive logic. Major Premise Minor Premise Conclusion +
Recall: Validity of a Deductive Argument An argument is valid if given the premises, the conclusion is guaranteed.
Is this argument valid? All mushrooms on the planet Qi are poisonous. Bell-bottoms are a type of mushroom in Qi. Therefore, Bell-bottoms in Qi are poisonous.
Is this argument valid? Some doctors are women. Some women are mothers. Therefore, some doctors are mothers.
Is this argument valid? Some A are B. Some doctors are women. Some B are C. Some women are mothers. Therefore, some doctors are mothers. Therefore, some A are C. Valid?
Is this argument valid? Some A are B. Some doctors are women. Some B are C. Some women are mothers. Therefore, some doctors are mothers. Therefore, some A are C. Valid?
Is this argument valid? Some A are B. Some doctors are women. Some B are C. Some women are mothers. Therefore, some doctors are mothers. Therefore, some A are C. A = Doctors B =Women Valid?
Is this argument valid? Some A are B. Some doctors are women. Some B are C. Some women are mothers. Therefore, some doctors are mothers. Therefore, some A are C. A = Doctors B =Women C = Mothers Valid?
Is this argument valid? Some A are B. Some doctors are women. Some B are C. Some women are mothers. Therefore, some doctors are mothers. Therefore, some A are C. A = Doctors B =Women C = Mothers Valid?
Same argument: Some A are B. Some cats are black. Some B are C. Some black things are televisions. Therefore, some A are C. Some cats are televisions. Not Valid!