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 :


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*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.

