Complex Numbers and their Properties

Imaginary numbers as we have discussed in Tuesday’s post are numbers of the form bi where b is a real number and i = \sqrt{-1}. The term imaginary as (opposed to real) was first used by Rene Descartes, the mathematician who invented Coordinate Geometry — the Cartesian plane in particular.  Leonhard Euler was the one who introduced the symbol i for \sqrt{-1}.

leonard euler

Leonhard Euler

Gerolamo Cardano, a pioneer in probability, was the one who suggested the   use of numbers of the form a + bi where a and b are real numbers and i = \sqrt{-1}.  Numbers of this form were named complex numbers by Carl Frederich Gauss.The real part of a + bi is a and the imaginary part is bi. » Read more