Real root isolation for tame elementary functions
Adam Strzeboński · 2009
We present a real root isolation procedure for univariate elementary functions. The procedure finds the domain and the zero set of a function f in an arbitrary, possibly unbounded, interval as long as f is represented by a tame expression. An elementary expression is tame if the arguments of its trigonometric subexpressions are bounded. We discuss implementation of the procedure and give empirical results. The procedure requires the ability to determine signs of elementary functions at simple roots of other elementary functions. The currently known method to do this depends on Schanuel's conjecture [7].