Someone recently asked me why a negative $\\times$ a negative is positive, and why a negative $\\times$ a positive is negative, etc. I went ahead and gave them a proof by contradiction like this: As...

Mar 13, 2011 · A reasonable place to start is to search "strictly positive" or "strictly negative" in your favorite academic search engine. Those terms are used when there must be no ambiguity in whether …

Feb 8, 2014 · In the set of real numbers, there is no negative zero. However, can you please verify if and why this is so? Is zero inherently "neutral"?

Apr 21, 2011 · The word is sign: In mathematics, the word sign refers to the property of being positive or negative. Every nonzero real number is either positive or negative, and therefore has a sign. Zero …

The word that you are looking for is the very word that you are using and that word is sign. If you are looking for something more "academic", then you can use its Latin variant, signum. Context can also …

Oct 31, 2014 · The product of a positive number and a negative number is negative, except when the positive number happens to be zero, in which case the result is zero, hence positive The emergence …

That is to say, the difference between positive and non-negative numbers is that for positive numbers it does not include zero, whereas for non-negative it does include zero.

51 The real numbers can be partitioned into the positive real numbers, the negative real numbers, and zero. A real number is one and only one of those three possibilities. This is called "trichotomy." Non …

For convenience, the square root of non-negative real numbers is usually taken to be the non-negative real value, but there is nothing other than practicality to stop you from taking some other pattern. …

Aug 11, 2014 · I've learnt in school that a positive number, when divided by a negative number, and vice-versa, will give us a negative number as a result.On the other hand, a negative number divided …