Complex Number

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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.

Complex number 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.


Gaussian Integer: A Gaussian integer is a complex number a + b i, where a and b are integers and i is the imaginary unit.
i: i is the symbol used to denote the principal square root of -1, also called the imaginary unit.


Imaginary Number: In mathematics, an imaginary number is multiple of the imaginary unit i (the square root of -1).
Real Number: A real number is a number corresponding to a point on the real number line.

Classroom Articles on Complex Numbers

  • Complex Conjugate
  • Complex Plane

  • 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