Complex numbers
Roots of a cubic equation
A cubic equation can have 3 real roots or 1 real root and a complex conjugate pair. In this video I show you how through the graphs of cubic equations. I then show you how to solve cubic equations that have complex roots by looking at this example:
- Find all the roots of the equation x3 - 4x2 + x + 26 = 0.
You are then given this question to try.
- Find all the roots of the equation x3 - 7x2 + 17x - 15 = 0.
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