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begin quote ita"
CHAPTER I [:] Notions from Set Theory [...] 2. OPERATIONS ON SETS. "end quote
These pages assume that the reader has the book and is reading along.    
topic index     contents
Please read these notes from the beginning to here, and then paragraphs 11 and 12 of 2.

THE CARTESIAN PRODUCT OF TWO SETS

The cartesian product of two sets will be so important to the real number system that I would like to repeat Rosenlicht's definition:

begin quote ita-1-2-11-pg7 "
Given two sets   X   and   Y   we define the cartesian product (or product) of   X   and   Y,   denoted   XY,   to be the set of all ordered pairs the first member of which is in   X,   the second in   Y,   that is   .
"end quote

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