Solving Rational Inequalities: x < 2/(5x-1) | My Final Answer Matches Textbook!

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SUMMARY

The discussion focuses on solving the rational inequality \(\frac{x}{2x-1} < -2\) and confirms that the solution is \( \frac{2}{5} < x < \frac{1}{2} \). The user expresses concern about whether to change the inequality sign during the solving process, particularly when substituting values like \(x = 1\). The final answer aligns with the textbook, affirming the correctness of the solution steps without needing to alter the inequality direction.

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odolwa99
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My final answer matches that of the textbook, but do I need to change the < to > at any point as I solve this? I ask because, if I assume x is 1 (until I solve for x), then the question statement and parts of the solution are made untrue.

Homework Statement



Solve the following for x [itex]\in\mathbb{R}:[/itex] [itex]\frac{x}{2x-1}<-2[/itex]

Homework Equations



The Attempt at a Solution



[itex]\frac{x(2x-1)^2}{2x-1}<-2(2x-1)^2[/itex]
[itex]x(2x-1)<-2(4x^2-4x+1)[/itex]
[itex]2x^2-x<-8x^2+8x-2[/itex]
[itex]10x^2-9x+2<0[/itex]
[itex](5x-2)(2x-1)=0[/itex]
[itex]x=\frac{2}{5}[/itex] or [itex]\frac{1}{2}[/itex]
[itex]\frac{2}{5}<x<\frac{1}{2}[/itex]
 
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hi odolwa99! :smile:
odolwa99 said:
… if I assume x is 1 (until I solve for x), then the question statement and parts of the solution are made untrue.

but 1 isn't between 2/5 and 1/2,

so why is that a difficulty? :confused:
 
Yeah, I'm just double checking my work so I can be absolutely sure I'm correct at all steps. Thanks for looking at it for me.
 

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