Union and Intersection
If A and B are disjoint sets, then
From this, one can show that in general the cardinalities of unions and intersections are related by
Read more about this topic: Cardinality
Famous quotes containing the words union and/or intersection:
“If the Union is now dissolved it does not prove that the experiment of popular government is a failure.... But the experiment of uniting free states and slaveholding states in one nation is, perhaps, a failure.... There probably is an “irrepressible conflict” between freedom and slavery. It may as well be admitted, and our new relations may as be formed with that as an admitted fact.”
—Rutherford Birchard Hayes (1822–1893)
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—Bill Bryson (b. 1951)