We establish an exact integral representation of the unique zero of a continuous function f on a,b satisfying f(a)>0, f(b)<0, and admitting exactly one zero in (a,b). The main result is the chain of equalities involving a double integral with two equivalent integration orders, related by the Fubini-Tonelli theorem. A numerical validation is provided.
Cheikh Ahmadou Bamba Tope (Fri,) studied this question.