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The Answer is Imaginary

Michael Alison Chandler, a Post reporter who is spending the year taking Algebra II and blogging about her experiences, has arrived at the part of the curriculum that includes imaginary numbers.

Not surprisingly, she has questions.

First off, why is the square root of -1 “imaginary”? If nothing times itself can equal a negative number, than how can these numbers exist at all?

Second, Why do we need them? When, on earth, would you ever want to use them?

A few commenters offer answers to her first group of questions.  I’ll bet they’re also covered in the textbook.

Those in the second group are questions that all students should be asking – and getting good answers to – when studying math at any level.

Largely, however, they don’t.

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1 Comment

  1. Dave

    In America, a lot of people have faith in a lot of things. Students having faith in math textbooks does not seem to be one of them.

    It’s an interesting idea: maybe the students who just trust that things like imaginary numbers are important and learn them are the ones who keep moving forward and do well enough to take the later classes where they use the imaginary numbers. The ones who stick on the “why” start falling behind and never end up getting an answer. Maybe.

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