diff --git a/guide/english/mathematics/complex-plane/index.md b/guide/english/mathematics/complex-plane/index.md new file mode 100644 index 0000000000..2a0dc27e32 --- /dev/null +++ b/guide/english/mathematics/complex-plane/index.md @@ -0,0 +1,37 @@ +--- +title: Complex Number Plane +--- + +## Complex Numbers + +The complex number plane expresses a complex number in graphical form. The complex number is an extension of the real number +line that adds an imaginary axis. This creates a two dimensional space with real and imaginary coordinates. + +Complex numbers take the form (a + bi) with the real part being "a" expressed on the x-axis and "b" expressed on the y-axis. See the +graph below. + + + +A complex number that is on the x-axis is called purely real; while a complex number that is on the y-axis only is +called purely imaginary. The x-axis or real number line includes all real numbers. Therefore, the set of all real numbers is actually +a subset of the complex numbers. All real numbers, then are complex numbers who imaginary component is zero. + +## Complex Polar Coordinates + +In polar form the cooordinates are the radius to the point in the complex plane and the angle from the x-axis. + +The radius[r] is found from the pythagorean formula applied to the real and imaginary componenets. + +r = sqrt(a^2 + b^2) + +The angle for the polar coordinate is found from taking the inverse tangent of the real and imaginary coordinates. + +@ = arctan(b/a) where x > 0 +@ = arctan(b/a) + pi where x < 0 +@ is undefined when x = 0 + + + +#### More Information +-[Wikipedia:Complex number](https://en.wikipedia.org/wiki/Complex_number) +-[Wolfram](http://mathworld.wolfram.com/ComplexNumber.html)