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

AI Thread Summary
The discussion centers on solving the rational inequality x/(2x-1) < -2 and verifying the solution. The final answer matches the textbook, identifying the solution interval as 2/5 < x < 1/2. A concern is raised about whether to change the inequality direction during the solving process, particularly when testing values like x = 1. It is clarified that since 1 is not within the solution interval, it does not affect the validity of the solution. The participant seeks confirmation to ensure all steps are accurate.
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 \in\mathbb{R}: \frac{x}{2x-1}&lt;-2

Homework Equations



The Attempt at a Solution



\frac{x(2x-1)^2}{2x-1}&lt;-2(2x-1)^2
x(2x-1)&lt;-2(4x^2-4x+1)
2x^2-x&lt;-8x^2+8x-2
10x^2-9x+2&lt;0
(5x-2)(2x-1)=0
x=\frac{2}{5} or \frac{1}{2}
\frac{2}{5}&lt;x&lt;\frac{1}{2}
 
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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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