Complex Inequality

Pronunciation: /kəmˈplɛks ˌɪn ɪˈkwɒl ɪ ti/ Explain

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Manipulative 1 - Complex Inequality Created with GeoGebra.

A complex inequality is two or more inequalities in a single statement. A complex inequality is a conjunction of two or more inequalities. This means that all the inequalities must be true at the same time. The complex inequality -2 < a ≤ 4 can also be written -2 < a and a ≤ 4.

Graphing Complex Inequalities

StepEquation(s)DescriptionGraph
1-2 < a ≤ 3This is the inequality to graphNumber line from -3 to 3.
2-2 < a ≤ 3Since -2 < a, -2 is not included in the inequality. Put a hollow dot at -2.Number line from -3 to 3 with a hollow dot at -2.
3-2 < a ≤ 3Since a ≤ 3, 3 is included in the inequality. Put a solid dot at 3.Number line from -3 to 3 with a hollow dot at -2 and a solid dot at 3.
4-2 < a ≤ 3The left-hand side of the inequality states that a member of the inequality must be greater than -2.Number line from -3 to 3 with a hollow dot at -2 and a solid dot at 3. A ray extends from -2 in the positive direction.
5-2 < a ≤ 3The right-hand side of the inequality states that a member of the inequality must be less than or equal to 3.Number line from -3 to 3 with a hollow dot at -2 and a solid dot at 3. A ray extends from -2 in the positive direction. A ray extends from 3 in the negative direction.
6-2 < a ≤ 3Any point that is included in the inequality must be in both rays, so draw a line segment for the points included in both rays.Number line from -3 to 3 with a hollow dot at -2 and a solid dot at 3. A ray extends from -2 in the positive direction. A ray extends from 3 in the negative direction. A line segment extends from -2 to 3.
7-2 < a ≤ 3Remove the extra rays.Number line from -3 to 3 with a hollow dot at -2 and a solid dot at 3. A line segment extends from -2 to 3.

References

  1. inequality. merriam-webster.com. Encyclopedia Britannica. Merriam-Webster. Last Accessed 8/6/2018. http://www.merriam-webster.com/dictionary/inequality.
  2. Bettinger, Alvin K. and Englund, John A.. Algebra and Trigonometry. pp 248-253. www.archive.org. International Textbook Company. January 1963. Last Accessed 8/6/2018. http://www.archive.org/stream/algebraandtrigon033520mbp#page/n265/mode/1up/search/inequality. Buy the book

More Information

  • McAdams, David E.. Inequality. allmathwords.org. All Math Words Encyclopedia. Life is a Story Problem LLC. 6/27/2018. http://www.allmathwords.org/en/i/inequality.html.

Cite this article as:

McAdams, David E. Complex Inequality. 6/25/2018. All Math Words Encyclopedia. Life is a Story Problem LLC. http://www.allmathwords.org/en/c/complexinequality.html.

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Revision History

6/25/2018: Removed broken links, updated license, implemented new markup, updated GeoGebra apps. (McAdams, David E.)
1/18/2010: Changed figure to GeoGebra application. (McAdams, David E.)
10/26/2009: Added additional description and 'Graphing Complex Inequalities'. (McAdams, David E.)
11/28/2008: Initial version. (McAdams, David E.)

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