Complex Numbers
Math · Advanced · Lesson 4 of 7

Euler’s Formula

e^(iπ) + 1 = 0

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

  • Euler's formula: eiθ=cos⁡θ+isin⁡θe^{i\theta} = \cos\theta + i\sin\theta.
  • eiπ+1=0e^{i\pi} + 1 = 0.
  • Any complex number is reiθre^{i\theta}: a length times a rotation.

Steps

  1. Exponentials that rotate
  2. Half a turn
  3. Quarter turn
  4. A sixth of a turn
  5. Length of an exponential
  6. i to the i