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<Michelangelo Ricci> investigated geometric problems of maxima and minima in the seventeenth century. A 1666 letter preserved by the Royal Society discusses his mathematical booklet and its argument concerning limits, providing contemporary evidence of its reception.https://catalogues.royalsociety.org/CalmView/Record.aspx?id=CLP%2F24%2F22&src=CalmView.Catalog[John Collins letter, 1666, discussion of Ricci's Exercitatio Geometrica]{ref}

A modern illustration of the relevant kind of <optimization> problem is to maximize $x^m(a-x)^n$ for $0<x<a$ and positive $m,n$. Differentiating its <logarithm> gives $m/x-n/(a-x)$, so the maximum occurs at $x=ma/(m+n)$. This calculation illustrates how a geometric extremum can become an algebraic relation; it does not attribute modern derivative notation to Ricci.


 Michelangelo Ricci (source code)