How to Solve Rational Inequalities?

AI Thread Summary
To solve the rational inequality (x+2)/(x+1) - 2 < 0, the correct approach involves simplifying the expression to (-x)/(x+1) < 0. There is confusion regarding the solution, as the expected answer is (4, 7], but calculations suggest it should be (-∞, -1) U (0, ∞). The discussion highlights a misunderstanding about the problem's nature, clarifying that it involves rational inequalities rather than absolute value inequalities. Participants confirm the need for careful interpretation of the inequality to arrive at the correct solution.
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Homework Statement



Solve (x+2)/(x+1) -2 < 0

Homework Equations



LCD: x + 1

The Attempt at a Solution



(x+2-2x-2)/(x+1) < 0

(-x )/(x+1) < 0

But somehow, I got the wrong answer. The answer is (4, 7]. But I don't know where I went wrong.
 
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I tried everything I could to answer this problem. Am i right that the lcd is x + 1? Because when i multiply - 2 by x + 1, i end up having to cross out + 2 and -2.
 
I'm confused because you title this thread "Absolute Value Inequalities," but your problem does not have any absolute value symbols. Can you double check the problem, please? Is the problem this?
\frac{x+2}{x+1} -2 &lt; 0
Because that's what I'm interpreting.

Furthermore, according to WolframAlpha, the solution to what I typed above is
(-∞, -1) U (0, ∞), not (4, 7].69
 


Your right, its not absolute inequalities. It's rational equalities.

Okay, thanks a lot for answering this question. I really do appreciate it.
 
I picked up this problem from the Schaum's series book titled "College Mathematics" by Ayres/Schmidt. It is a solved problem in the book. But what surprised me was that the solution to this problem was given in one line without any explanation. I could, therefore, not understand how the given one-line solution was reached. The one-line solution in the book says: The equation is ##x \cos{\omega} +y \sin{\omega} - 5 = 0##, ##\omega## being the parameter. From my side, the only thing I could...

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