Complex Plane

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The complex plane is a term for the set of all complex numbers. Just as all real numbers can be imagined as lying on a line, all complex numbers can be thought of as points in a plane.

Complex plane is a high school-level concept that would be first encountered in a pre-calculus course covering complex numbers. It is listed in the California State Standards for Algebra II.


Cartesian Coordinates: Cartesian coordinates are the usual coordinate system, originally described by Descartes, in which points are specified as distances to a set of perpendicular axes. Also called rectangular coordinates.
Complex Number: A complex number is a number consisting of a real part and an imaginary part. A complex number is an element of the complex plane.
Real Number: A real number is a number corresponding to a point on the real number line.

Classroom Articles on Complex Numbers

  • Complex Conjugate
  • i
  • Imaginary Number

  • Classroom Articles on Pre-Calculus (Up to High School Level)

  • Asymptote
  • Normal Vector
  • Conic Section
  • Parabola
  • Cross Product
  • Parametric Equations
  • Curve
  • Plane
  • Determinant
  • Plane Curve
  • Domain
  • Polar Coordinates
  • Dot Product
  • Range
  • e
  • Rational Function
  • Ellipse
  • Reflection
  • Exponential Function
  • Rotation
  • Function
  • Rotation Matrix
  • Hyperbola
  • Scalar
  • Inverse Function
  • Spherical Coordinates
  • Locus
  • Tangent Line
  • Logarithm
  • Translation
  • Natural Logarithm
  • Vector