Electronic Proceedings of the Twentyfourth Annual International Conference on Technology in Collegiate MathematicsOrlando, Florida, March 2225, 2012Paper C036
This is an electronic reprint, reproduced by permission of Pearson Education Inc. Originally appeared in the Proceedings of the Twentyfourth Annual International Conference on Technology in Collegiate Mathematics, ISBN 0321869699, Copyright (C) 2013 by Pearson Education, Inc. 
On the Casus Irreducibilis of Solving the Cubic Equation 
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We often encounter the cubic equation. Its roots can be found using Cardan's formula. The curious fact is that when all roots are real and the cubic polynomial is irreducible, the real roots are expressed in terms of radicals of complex quantities. This case is discussed and examples provided.
Keyword(s): real analysis