Question 528207
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13 is in the sets of Counting, Natural, Whole, Integer, Rational, and Real numbers.


Some authors will say that Counting numbers start at 1, while Natural numbers start at zero, but this is by no means consistent amoung mathematical authors.  Also Whole numbers are thought by some to be equivalent to Natural numbers, i.e. inclusive of zero but exclusive of the negatives, whereas some authors insist that Whole numbers are equivalent to the Integers, i.e., inclusive of both zero and the negatives.  Ask your teacher/instructor/professor how s/he defines the terms and use those same definitions as long as you are subject to the grading whims of that particular educator.  Be prepared to change your definition as you progress through your mathematical education.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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