Different Types of Numbers
Date: 4/13/96 at 21:36:37 From: Anonymous Subject: Reals, intergers, whatever... I don't understand how to tell the difference between the different kinds of numbers. i.e. reals, integers, and stuff, and I was hoping you could help me.
Date: 4/14/96 at 1:21:51 From: Doctor John Subject: Re: Reals, integers, whatever... Whole numbers are the numbers you use when you count: 0,1,2,3,... Integers are all of the whole numbers and their negatives. They are ...-3,-2,-1,0,1,2,3,... (The three dots means you keep going in both directions.) There are also rational numbers. Rational numbers are all the different kinds of fractions. 1/2, 3/4, -2/3, and 5 are all rational numbers. Irrational numbers are numbers which you can write as decimals but not as fractions. Pi and the square root of 2 are irrational numbers. Real numbers are all of the rational and all of the irrational numbers put together. All of the numbers you normally deal with are real numbers. (There are also other kinds of numbers called imaginary numbers, but don't worry about those right now.) -Doctor John, The Math Forum
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