Inclusion-exclusion principle
= Inclusion-exclusion principle
{wiki}
= Inclusion-exclusion
{synonym}
For finite sets $A_1,\ldots,A_n$, the cardinality of their union is the alternating sum of the cardinalities of their nonempty intersections.
= Inclusion-exclusion principle
{wiki}
= Inclusion-exclusion
{synonym}
For finite sets $A_1,\ldots,A_n$, the cardinality of their union is the alternating sum of the cardinalities of their nonempty intersections.