Negations

Lessons

• Introduction
  Negations Overview:
  a)

  Definition of Negations and Examples
  
  

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• 1.
  Negation of the Statement

  Write the negation of each statement:

  a)

  The sun rises from the east.
  
  
  b)

  $1+1=0$
  
  
  c)

  January is the first month of the year.
  
  
  d)

  The Eiffel Tower is in Japan.
  
  
  e)

  A square has 7 sides.
  
  

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• 2.
  Truth Value of a Negation

  Write the negation of each statement, and determine the truth value:

  a)

  A snake is a reptile.
  
  
  b)

  The measure of an acute angle is greater than 90°.
  
  
  c)

  $5+5+5=555$
  
  
  d)

  $\frac{5}{6}$ is a fraction.
  
  

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• 3.
  The symbols represent the following statements

  $p$: A pentagon has 5 sides
  $q$: United States is a city
  $r$: Chairs have four legs

  Write a complete sentence in words to show what the symbols means, and find the truth value:

  i) ~$p$
  ii) ~$q$
  iii) ~$r$

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• 4.
  Double Negation

  Determine the truth value of the statement. Negate it twice, write it in a complete sentence, and determine the new truth value:

  a)

  A quarter of an hour is 15 minutes
  
  
  b)

  There is caffeine in coffee.
  
  
  c)

  The ocean has salt water.
  
  

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