Universal sets like cool math games

Universal Sets of cool math for kids

 

 A set that contains everything. Well, not exactly everything. Everything that is relevant to the problem you have.

So far, all I've been giving you in sets are integers. So the universal set for all of this discussion could be said to be integers. In fact, when doing Number Theory, this is almost always what the universal set is, as Number Theory is simply the study of integers.

However in Calculus (also known as real analysis), the universal set is almost always the real numbers. And in complex analysis, you guessed it, the universal set is the complex numbers.

More Notation: 

Also, when we say an element a is in a set A, we use the symbol to show it.
And if something is not in a set use .

Example: Set A is {1,2,3}. You can see that 1 A, but 5 A

 

=====================