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
.
.
.
.
.
.
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.
.
.
.
|
|
|