There's a mistake on the CTK-wiki page about the Tartaglia-Cardano derivation of the solution to cubic equations.The derivation sets x = p - q, then correctly proceeds to find p and q.
At the very last step there is a sign error on the q term and both p and q are written the same, so that in the final formula for the solution the two complicated terms cancel and give 0.
Would someone with edit power please make the simple change and put the - sign in front of b/2 in the second term of this equation, so the final formula is correct?
Thanks,
Bryan
https://www.cut-the-knot.org/wiki-math/index.php?n=Mathematics.Tartaglia-CardanoDerivation
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