Linear Inequalities: Error in book?

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Discussion Overview

The discussion revolves around the correct interval notation for the inequality \(x \leq -2\), comparing a participant's answer with that provided in a textbook. The focus is on identifying potential errors in the book's content.

Discussion Character

  • Debate/contested

Main Points Raised

  • One participant claims the correct interval notation is \((- \infty, -2]\).
  • Another participant agrees, suggesting the book's answer of \((\infty, -2]\) is a typo.
  • A third participant expresses frustration with the frequency of errors in the book, implying it undermines confidence in solving problems.
  • A fourth participant asserts that such an error must be a typo, as it does not make logical sense.

Areas of Agreement / Disagreement

Participants generally agree that the book contains a typo regarding the interval notation, but there is no formal consensus on the overall reliability of the book.

Contextual Notes

Participants express concerns about the prevalence of errors in the textbook, which may affect their confidence in the material.

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Give the interval notation for the inequality: [tex]\displaystyle{x\leq -2[/tex]

My answer is: [tex]\displaystyle{(-\infty, -2]}[/tex]

Book answer is: [tex]\displaystyle{(\infty, -2]}[/tex]

?
 
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You're right. Looks like a typo in the book.
 
mathman said:
You're right. Looks like a typo in the book.


Thanks. This book is absolutely riddled with errors of this type; enough to make you often doubt yourself after successfully completing some problems.

I hope the editor doesn't have any competition...:rolleyes:
 
When you read stuff like that you should know that it has to be a typo, because you know that it cannot make sense.
 

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