In some cases, a square root of a negative number must exist in order to determine the roots of a cubic equation. An educational presentation provides a specific example of a cubic with a known root to have an understanding of a square root of a negative number.
- Have the class use del Ferro's formula presented in the video to confirm roots of cubic functions
- Research Cardan's formula for cubic equations that include the x squared term and confirm that it works for cubics with real roots
- Second video in a nine-part series
- Provides a historical view of why being able to take a square root of a negative number was necessary
- Continues the progression of the history of complex numbers from the first video