Expert: Sherry Wallin - 4/23/2011

Question
true or false

the product of two rational numbers is always a rational number

Answer
Lucille~

Absolutely! Do you need to prove it? Here is the reason why:
the smallest set of numbers are the 'natural numbers = {1,2,3,...}
and then comes the whole numbers which is 0 plus the natural numbers: {0,1,2,...}
and then the integers: {...,-3,.2,.1,0,1,2,3,...}
and then we have rational numbers which are described as all those numbers that can be written as a fraction of integers, or like a/b where both a,b are integers and b ~=0. And finally the irrational numbers do not have anything in common with any of the above numbers but if you take all the above numbers and combine them with the irrational numbers then you have the real numbers...

Math Prof