Area of Common Overlap of Three Circles

摘要

This Note presents the unsolved to an apparent hitherto tin solved geometrical problem: the derivation of a closed-form algebraic expression of the area of common overlap of three circles, such as can occur a three-circle Venn diagram. The results presented here have general significance in the corpus of menstruation formulae, and could be of specific use in any quantitative application of the three-circle Venn diagram such as for example, in search and screening problems.