Friday, July 15, 2016

Names for Inequalities

Consider an inequality of the form a < x < b, that is, a < x and x < b. Trying to find a name for this type of inequality, I'm finding a thicket of different terminology:
  • Chained inequalities (Wikipedia). 
  • Combined inequalities (Sullivan Algebra & Trigonometry).
  • Compound Inequalities (Ratti & McWatters Precalculus, Bittinger Intermediate Algebra, OpenStax College Algebra).

Are there more? What is most common in your experience?


  1. "Inequality between more than two things?" Those terms make them sound like second-class citizens.

    1. Well, admittedly the expression needs to be defined in terms of simpler inequalities (with an "and" conjunction). For example: a < b is legitimate syntax in any programming language, but a < x < b is not.