31.6.2 Complex Roots of Real-Coefficient Equations
Core ideaPicture this: rewrite √(negative) as i√(positive) and a quadratic always yields a pair of complex roots, x=(−b±i√(−Δ))/(2a)
Module goal. We use complex numbers to complete the roots of real-coefficient equations, reclaiming what a negative discriminant used to cost us, and paving the way for counting and polynomials ahead