I honestly cannot believe I am stuck on this.

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The discussion revolves around solving the inequality |5/(x + 2)| < 1, with participants clarifying the steps involved. The key point is that the expression is undefined at x = -2, which must be excluded from the solution. The correct approach involves setting up two inequalities derived from the absolute value, leading to the intervals x < -7 and x > 3. Participants emphasize the importance of correctly applying the properties of absolute values and suggest visualizing the function to better understand the solution. The final takeaway is that the solution requires careful handling of discontinuities and the properties of inequalities.
flyingpig
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Homework Statement




Solve

\left | \frac{5}{x + 2} \right | &lt; 1

The Attempt at a Solution



All I know is that x= -2 is discontinuous. I thought about doing test points, but it seemed rather useless seeing I will probably end up with (-2, infinity) or (-inf, -2)

Computer says the solution is x < -7, x >3

I then thought about doing this

\left |5\right | &lt; \left|x + 2\right|
-|x + 2| &lt; -5
5 &lt; -(x + 2) &lt; -5
-5 &gt; x + 2 &gt; 5
-7 &gt; x &gt; 3

I am sorry lol
 
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I don't understand how you get the third step? :confused:

You should go by taking two cases.
What do get when you solve |x+2|? Definitely (x+2) and -(x+2). :smile:

If you solve these two equations:-
5<(x+2)
and
5<-(x+2)
You will get the desired result. :smile:
 
-7 &gt; x &gt; 3

?

x is greater than 3 and less than -7?
 
See I don't know what I am doing lol
 
flyingpig said:
See I don't know what I am doing lol

You can set up two inequalities (see Pranav-Anora's post). Or you can set up a double inequality since this problem is of the "less-than" variety. You attempted to do the double inequality method, but you shouldn't have a negative on your absolute value expression. I think you mixed two different methods into one. :wink:

Here's a general example of how you should've setup the double inequality:

Given |expression| < k, set up the double inequality, -k < |expression| < k and solve.
 
flyingpig said:
See I don't know what I am doing lol

Why don't you try making a sketch of y= |5/(x+2)| and y=1 on the same set of axes.
 
flyingpig said:
Solve

\left | \frac{5}{x + 2} \right | &lt; 1

The Attempt at a Solution



All I know is that x= -2 is discontinuous.
No, the rational expression is undefined at x = -2.
flyingpig said:
I then thought about doing this

\left |5\right | &lt; \left|x + 2\right|
Your inequality is equivalent to
|x + 2| > 5 and x \neq -2

In general, if you have an inequality of the form |x + a| > b, you can get rid of the absolute values by rewriting this as
x + a > b or x + a < - b

For your problem, since x cannot be -2, any interval you end up with cannot include -2.
 
flyingpig said:

Homework Statement




Solve

\left | \frac{5}{x + 2} \right | &lt; 1

The Attempt at a Solution



All I know is that x= -2 is discontinuous. I thought about doing test points, but it seemed rather useless seeing I will probably end up with (-2, infinity) or (-inf, -2)

Computer says the solution is x < -7, x >3

I then thought about doing this

\left |5\right | &lt; \left|x + 2\right|
-|x + 2| &lt; -5
5 &lt; -(x + 2) &lt; -5
-5 &gt; x + 2 &gt; 5
-7 &gt; x &gt; 3

I am sorry lol

For real A, the inequality |A| < 1 is the same as -1 < A < 1.

RGV
 

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