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:
“My paramount object in this struggle is to save the Union, and is not either to save or to destroy slavery. If I could save the Union without freeing any slave, I would do it; and if I could save it by freeing all the slaves, I would do it; and if I could save it by freeing some and leaving others alone, I would also do that.”
—Abraham Lincoln (1809–1865)
“If we are a metaphor of the universe, the human couple is the metaphor par excellence, the point of intersection of all forces and the seed of all forms. The couple is time recaptured, the return to the time before time.”
—Octavio Paz (b. 1914)