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| Question 327127:  Find and Graph the solution set.
 a. x^3-16x>0
 b. x^2-5x<=-6
 Answer by Fombitz(32388)
      (Show Source): 
You can put this solution on YOUR website!  
  
  Break up the number line into 4 regions:
 Region 1 : (
  ,  ) Region 2 : (
  ,  ) Region 3 : (
  ,  ) Region 4 : (
  ,  ) Choose a point in the region (not an endpoint).
 Test the inequality.
 If the inequality is satisfied, the region is part of the solution.
 .
 .
 .
 Region 1:
  
  
  
  False, this region is not part of the solution.
 .
 .
 .
 Region 2:
  
  
  
  True, this region is part of the solution.
 .
 .
 .
 Region 3:
  
  
  
  False, this region is not part of the solution.
 .
 .
 .
 Region 4:
  
  
  
  True, this region is part of the solution.
 .
 .
 .
 The solution region is (
  ,  ) U (  ,  ). .
 .
 .
 Verified graphically
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 .
 
   .
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 .
 Similarly,
 
  
  
  Break up the number line into 3 regions:
 Region 1 : (
  ,  ) Region 2 : (
  ,  ) Region 3 : (
  ,  ) Choose a point in the region (not an endpoint).
 Test the inequality.
 If the inequality is satisfied, the region is part of the solution.
 .
 .
 .
 Region 1:
  
  
  
  True, this region is part of the solution.
 .
 .
 .
 Region 1:
  
  
  
  False, this region is not part of the solution.
 .
 .
 .
 Region 2:
  
  
  
  True, this region is part of the solution.
 .
 .
 .
 Region 3:
  
  
  
  False, this region is not part of the solution.
 .
 .
 .
 The solution region is [
  ,  ]. Since the inequality includes the "=" the brackets denote that 2 and 3 are included as part of the solution.
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