Skip to main content

The Imaginary Unit

This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.

State

The imaginary unit i is defined as the square root of −1, so that i² = −1; i is the principal, positive root.

Show

No real number squares to a negative, so i lives off the real line — a new number admitted under the old rules.

Watch for

i is a number, not a variable.

Builds on

  • Nothing — this is a starting point.

Unlocks

  • Nothing yet depends on this.