#Imaginary numbers how to#
When learning in primary school the job of subtracting numbers, a typically curious child may ask the teacher how to subtract, say, six from four.
![imaginary numbers imaginary numbers](http://www2.clarku.edu/~djoyce/complex/powers2.gif)
Think, in the first place, about the negative numbers. The truth is that when one is introduced to imaginary numbers, it’s not the first time that a fundamental idea previously taught, is turned upside down. Now we are told that this is not always the case, and here we have this ‘number’ for which the rule does not hold? What kind of number is this if it breaks such a fundamental law about the multiplication of numbers? Is the mystery and the apparent contradiction solved just by calling i an ‘imaginary number’? How come? We were consistently told in the early years of secondary school that two numbers of the same sign, positive or negative, when multiplied by each other always yield a positive number. This symbol is used to denote the idea of, namely, a number that when multiplied by itself yields -1.
![imaginary numbers imaginary numbers](https://i.ytimg.com/vi/mfoOYdDkuyY/maxresdefault.jpg)
In this second post, looking specifically at the impact of imaginary numbers on our comprehension of the physical world, Leo explores how theorems change over time.įew elementary mathematical ideas arouse the kind of curiosity and astonishment among the uninitiated as does the idea of the ‘imaginary numbers’, an idea embodied in the somewhat mysterious number i.
![imaginary numbers imaginary numbers](http://drralph.pbworks.com/f/1448762909/b1.jpg)
In this blog series, Leo Corry, author of A Brief History of Numbers, helps us understand how the history of mathematics can be harnessed to develop modern-day applications today.