Chemistry Reference and  Research
           
 
Periodic Table
- standard table
- large table
 
Chemical Elements
- by name
- by symbol
- by atomic number
 
Chemical Properties
 
Chemical Reactions
 
Organic Chemistry
 
Branches of Chemistry
Analytical chemistry
Biochemistry
Computational Chemistry
Electrochemistry
Environmental chemistry
Geochemistry
Inorganic chemistry
Materials science
Medicinal chemistry
Nuclear chemistry
Organic chemistry
Pharmacology
Physical chemistry
Polymer chemistry
Supramolecular Chemistry
Thermochemistry

Category:Numbers

A number is an abstract entity used to describe quantity. There are different types of numbers. The most familiar numbers are the natural numbers {0, 1, 2, ...} used for counting and denoted by N. If the negative whole numbers are included, one obtains the integers Z. Ratios of integers are called rational numbers or fractions; the set of all rational numbers is denoted by Q. If all infinite and non-repeating decimal expansions are included, one obtains the real numbers R. Those real numbers which are not rational are called irrational numbers. The real numbers are in turn extended to the complex numbers C in order to be able to solve all algebraic equations. The above symbols are often written in blackboard bold, thus:

\mathbb{N}\sub\mathbb{Z}\sub\mathbb{Q}\sub\mathbb{R}\sub\mathbb{C}


See also


Subcategories

There are 12 subcategories to this category.
  • Cardinal numbers
  • Complex numbers
  • Constants
  • D

    F

    I

    L

    N

    N cont.

    R

    Articles in category "Numbers"

    There are 27 articles in this category.
  • Baker's dozen
  • C

    D

    F

    H

    I

    M

    N

    O

    P

    P cont.

    R

    S

    T

    01-04-2007 01:16:19
    The contents of this article are licensed from Wikipedia.org under the GNU Free Documentation License. How to see transparent copy