5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
5­4 Inverses and Contrapositives
Objectives: 1. Write the negation of a statement.
2. Write the inverse and contrapositive of a conditional statement.
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5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
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5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
When a statement is false,
Fort Collins is the capital of Colorado.
the NEGATION of the statement is true.
Fort Collins is NOT the capital of Colorado. Sep 6­3:19 PM
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5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
Write the negation of each statement.
a. Angle ABC is obtuse.
b. Today is not Tuesday.
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5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
Writing Inverse and Contrapositive
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5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
Write the converse, inverse, and contrapositive of the following conditional.
Conditional: If you don't stand for something, you'll fall for anything.
Converse:
Inverse:
Contrapositive:
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5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
Write the converse, inverse, and contrapositive of the following conditional.
Conditional: If it's raining outside, then the sidewalks are wet.
Converse:
Inverse:
Contrapositive:
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5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
A conditional and its contrapositive will ALWAYS have the same truth value.
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5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
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5.4 (after 2.1) Inverses and Contrapositives 2010 September 10, 2010
Homework
p. 283 #1­9, 34­37, 42­45
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