Multiple index entry

I want to know what is the proper way to do multiple indexes in languages where the adjectives come after the subject. For example in english if I want to index the inverse function I can do:

index{function!inverse}
index{inverse function}

In spanish, for example, it could be:

index{función!inversa}
index{inversa}
index{inversa@función inversa}
index{inversa@(función) inversa}
index{inversa@función inversa}
index{inversa@función inversa}
index{inversa|see{función}}
index{inversa|seealso{función}}

I don’t want to use the see and seealso ways. How is this usually done?

documentclass[a4paper]{book}
usepackage[T1]{fontenc}
usepackage[spanish]{babel}

usepackage{imakeidx}

makeindex

begin{document}

section{Función}

index{integral}
index{série}
index{cálculo}

index{función}
index{función!inversa}

printindex

end{document}