Imaginary Numbers

The symbol i represents something that, when squared, is equal to negative 1.

i^2 = -1

Because of this property we see math such as the following:

(3i)^2 = -9

An imaginary number may be the summation of an imaginary component and a real component:

x = 3i + 4

The above has an imaginary component of 3 and a real component of 4.

We might think of a real number as being an imaginary number with a imaginary component of zero.

x = 0i + 4

There is a progression or pattern as we take exponents of i with increasing power:

  • i^0 = 1
  • i^1 = i
  • i^2 = -1
  • i^3 = -i
  • i^4 = 1
  • i^5 = i
  • i^6 = -1
  • the pattern continues…