Variations on products and quotients of Darboux functions
A. M. Bruckner and the reviewer proved that if a Darboux function f: \(R\to R\) is constant on no subinterval and D is a countable dense subset of R, then there exists a function g taking on all values in each interval such that the range of \(f+g\) is D. This paper contains a number of variants of this result replacing sums by products and quotients, considering the domain of f to be various subsets of R and letting g take on each value c-times in each interval. In particular, there is a characterization of those functions which can be a quotient of Darboux functions. (This corrects an assertion of the reviewer.)
scientific article; zbMATH DE number 4168971