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Complex Number Calculator

Perform arithmetic operations on complex numbers, convert between rectangular and polar forms, calculate powers using De Moivre's theorem, and find all nth roots.

Complex Arithmetic

Add, subtract, multiply, divide complex numbers or find conjugate

How to Use the Complex Number Calculator

Enter complex numbers in rectangular form (a + bi) by providing the real and imaginary parts separately. Select the operation type and click Calculate to see results in multiple formats.

Calculator Modes

Arithmetic Operations

Perform basic operations on two complex numbers:

  • Addition: (a + bi) + (c + di) = (a+c) + (b+d)i
  • Subtraction: (a + bi) - (c + di) = (a-c) + (b-d)i
  • Multiplication: (a + bi)(c + di) = (ac-bd) + (ad+bc)i
  • Division: Uses the conjugate to rationalize the denominator
  • Conjugate: The conjugate of (a + bi) is (a - bi)

Form Conversion

Convert between three representations of complex numbers:

  • Rectangular: a + bi (Cartesian form)
  • Polar: r ∠ θ where r is magnitude and θ is angle
  • Exponential: re^(iθ) using Euler's formula

Powers (De Moivre's Theorem)

Raise a complex number to any integer power. De Moivre's theorem states: (r∠θ)^n = r^n ∠ nθ. This makes power calculations much simpler in polar form.

Roots

Find all n distinct nth roots of a complex number. A complex number has exactly n nth roots, evenly spaced around a circle in the complex plane.

What is a Complex Number?

A complex number has the form a + bi, where a is the real part, b is the imaginary part, and i is the imaginary unit (i² = -1). Complex numbers extend the real numbers and are essential in many areas of mathematics, physics, and engineering.

Common Applications

  • Electrical engineering (AC circuit analysis)
  • Signal processing and Fourier transforms
  • Quantum mechanics
  • Control systems
  • Fractal geometry (Mandelbrot set)

Key Formulas

  • Magnitude: |z| = √(a² + b²)
  • Angle: θ = arctan(b/a)
  • Euler's formula: e^(iθ) = cos(θ) + i·sin(θ)