what is a set?

Question

pls help me with my homework?? can you give me websites where i can find SET in algebra... and what are THE KINDS OF SET???

Answer 1

A set is any well defined collection of items.
Well defined means that you can tell definitely whether or not something is in a set.
For example, the collection of all objects on my desk is a set because one can tell definitely whether or not an item is on my desk.
The collection of all ghosts in New Orleans is not a set because one cannot tell definitely whether there are any ghosts, or which ghosts (if any) qualify.
Sets can be infinite or finite. The set of all integers is a set even though it is infinite, because it is well defined. The coollection of all "pretty numbers" is not a set because it is not well defined.
Set elements don't have to be numbers or concrete things, although if you want to get into abstractions you have to stick to the requirement that elements be well defined. Otherwise we have paradoxes and arguements that serve only to waste time and energy.
For more info see
http://www.geocities.com/basicmathsets/
If you don't like that one, put set theory tutorial in your search window and see what comes up. Set theory can be explained on all sorts of levels, from grade school to postgraduate. So some of the links may be way too technical. The one I've cited is a good one for starters, try others if that one doesn't work.
Good luck!

Answer 2

Here are some sets:

The set of even numbers: {..., -6, -4, -2, 0, 2, 4, 6, ...}
odd numbers: {... -5. -3, -1, 1, 3, 5, ...}
counting numbers: {1, 2, 3, 4, 5, ...}
positive single digit numbers: {1, 2, 3, 4, 5, 6, 7, 8, 9}
factors of 10: {1, 2, 5, 10}
the empty set: { }

Other common sets include the whole numbers, integers, rational numbers, irrational numbers, and the real numbers.

Notice that sets can be infinite (you can't count how many things are in the set), or finite (you can count and tell me how many items -- we call them elements or members -- the set has).

Also, sets may contain seemingly random elements. However, the ORDER of the members of a set is not important.

One last thing, sets can contain things that are not numbers. It could be the set of vehicles made by Dodge, the set of colors in a box of crayons, or the set of ordered pairs that you need to graph.

I hope this helps!

Answer 3

A group of numbers or items.

Mathematically we have
natural numbers {1,2,3,4...}
Whole numbers {0,1,2,3,4}
Integers {...-2, -1, 0, 1, 2, 3, 4}
Rational numbers {... -1, -1/2,0,1/2, 1...} (Any terminating fraction such as 0.5)
Irrational numbers {...-1,-1/3,0,1/3,1} (Any non-terminating fraction such as 0.333333......)
Real numbers (Rational and irrational numbers together)

Complex numbers- this is a bit tricky. When you do certain equations you will find that you have to get the square root of -1, which is impossible in the real numbering system. The complex, or "imaginary" is that number system and it is defined as the union of the Real numbers plus multiples of 1i. The "i" in this case is a symbol like + or -

Answer 4

In abstract algebra (and topology and others), a set is a collection of objects (or items or numbers).

Answer 5

Look up SET Theory.
Here is a good site: http://www.answers.com/set+theory?gwp=11&ver=2.1.1.521&method=3

Answer 6

Hope this website helps. It has a tutorial as well.

Answer 7

hmmmm.... we have that homework too... hope you let us copy yours when you got some answers! hehehehe!! LSC boyz...

Answer 8

set is a set duhhh!!!!

Answer 9

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