A question about the term "depressed cubic" The depressed cubic equation is a cubic equation of the form $x^3+px+q=0$. This expression sounds strange especially for someone that English is not his mother tongue. Why this equation is called "depressed"? What is so depressing in it? Thanks!

> Why this equation is called "depressed"?

It is from latin deprimitur : _lowered_.

It seems that the terminology was intoduced by François Viète (1540 – 1603) into his posthumous :

* Francisci Vietae Fontenaeensis ab aequationum recognitione et emendatione (1615), page 79:



> Anastrophe [ _anastrophe_ ] is the transformation of inverse negative equations into their correlatives. It is carried out so that the original equation, with the help of its correlative, can be reduced [ _reducatur ad depressiorem_ ] [...] to a lower [power] and, therefore, be more easily solved. [...] The work of anastrophe is performed this way : [...] and the equation, otherwise soluble only with difficulty, can depressed [ _deprimitur_ ] to one that is easily solved by means of a pretty operation.