SOLUTION: |2x-5|/|2x-1|<1/2 I need you to list solution in interval notation pls. Tnx

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Question 172028: |2x-5|/|2x-1|<1/2 I need you to list solution in interval notation pls. Tnx
Answer by Edwin McCravy(20086) About Me  (Show Source):
You can put this solution on YOUR website!
|2x-5|/|2x-1|<1/2 I need you to list solution in interval notation pls. Tnx


We get 0 on the right by subtracting 2 from both sides:

abs%282x-5%29%2Fabs%282x-1%29%3C1%2F2

We first find the endpoints by solving the equation:

abs%282x-5%29%2Fabs%282x-1%29=1%2F2

Which involves solving two equations:

%282x-5%29%2F%282x-1%29=1%2F2 and %282x-5%29%2F%282x-1%29=-1%2F2 

The first gives solution x=9%2F2 and the second gives
solution 11/6

9%2F2 is about 4.5 and {{11/6}}} is about 1.8333···

Mark those on a number line:

-------------------------o---------------o---------
-2     -1     0     1     2     3     4     5     6 

Test a value to the left of 11%2F6. The easiest
value is 0.  Substitute it into the original
inequality:

abs%282x-5%29%2Fabs%282x-1%29%3C1%2F2
abs%282%280%29-5%29%2Fabs%282%280%29-1%29%3C1%2F2
abs%28-5%29%2Fabs%28-1%29%3C1%2F2
5%2F1%3C1%2F2
5%3C1%2F2

That is clearly false so do not shade the part to the
left of 11%2F2.  So we still have just:

-------------------------o---------------o---------
-2     -1     0     1     2     3     4     5     6 

Now test a value between 11%2F6 and 9%2F2.
The easiest value is 2.  Substitute it into the original
inequality:

abs%282x-5%29%2Fabs%282x-1%29%3C1%2F2
abs%282%282%29-5%29%2Fabs%282%282%29-1%29%3C1%2F2
abs%284-5%29%2Fabs%284-1%29%3C1%2F2
abs%28-1%29%2Fabs%283%29%3C1%2F2
1%2F3%3C1%2F2

That is true so we do shade the part between
11%2F6 and 9%2F2.  Now we have this:

-------------------------o===============o---------
-2     -1     0     1     2     3     4     5     6

Now we test a value to the right of 9%2F2. The easiest
value is 5.  Substitute it into the original
inequality:

abs%282x-5%29%2Fabs%282x-1%29%3C1%2F2
abs%282%285%29-5%29%2Fabs%282%285%29-1%29%3C1%2F2
abs%2810-5%29%2Fabs%2810-1%29%3C1%2F2
abs%285%29%2Fabs%289%29%3C1%2F2
5%2F9%3C1%2F2

That is clearly false so do not shade the part to the
rightt of 9%2F2.

So the graph of the solution is

-------------------------o===============o---------
-2     -1     0     1     2     3     4     5     6

and the interval notation is

%28matrix%281%2C3%2C+11%2F6%2C++%22%2C%22%2C+9%2F2%29%29

Edwin