1 (Arabic numerals)
① (Arabic numeral serial number)
1. (Arabic numerals with dots)
(1) (Arabic numerals in brackets)
I (Simplified Chinese)
I (Simplified Chinese with brackets)
I (Traditional Chinese)
I (Roman numerals)
One course (English)
In mathematics
1, Arabic numerals.
2 is a natural number between 0 and 2.
3, odd number.
4, the second smallest positive integer.
5, neither prime number nor composite number.
6, any number divided by 1 is equal to itself.
Lowercase:
1
Chinese pinyin writing:
one
Capitalized:
one
English: one (cardinal word, one) first (ordinal number, first).
carry system
Counting symbol
Roman numeral
I
binary system
1
hexadecimal
1
Octal
1
A whole consisting of one or several things can be regarded as the unit "1".
In the field of science,
In computer science, 1 is often used to express -{zh-cn: Boolean value; True value of zh-tw: Boolean value}-.
In computer science, 1 is often used to represent the "true" value of a Boolean value.
In geometrical optics, the refractive index of vacuum is 1.
Astronomically, the average distance between the sun and the earth is 1 astronomical unit.
In human culture,
The ancient writing of "Yi" is "Mi". In Chinese dictionaries with radical indexing as the main index, "Yi" is often the first radical and the first word.
In human culture, the word "one" gives the meaning of the beginning of all things: "Tai Chi is the only beginning, Tao stands in one, heaven and earth are divided into all things, and all things are unified" (Shuo Wen Jie Zi).
In English, "freshman" is also used to refer to the Lord God in the Bible.
The basic denomination of currency, such as USD 1, NT 1 Yuan.
In music theory, the do sound on the score is represented by 1.
In philosophy, especially in Laozi, one is relatively extensive. "Tao gives birth to one, life gives birth to two, life gives birth to three, and life gives birth to everything. Everything is negative and holds yang, thinking that it is harmonious. " (Chapter 42 of Laozi) is one of them. The first is the beginning of everything. Ancient philosophers regarded one as the beginning of all things and called it Tai Chi. "Tai Chi gives birth to two instruments, two instruments give birth to four elephants, and four elephants give birth to gossip."
Moreover, among the ancient gods in China, the Eastern Emperor Taiyi was regarded as a great god. In Qu Yuan's Lisao, there is a poem about the Eastern Emperor Taiyi.
"One" can also be used as a unit of some constants, such as moles.
1 means the person who plays the male role among comrades, and 0 means the person who plays the female role.
Table-Integer
& lt& lt0 1 2 3 4 5 6 7 8 9 >； & gt
Mathematical attribute
1^n= 1
n/n= 1
(a/b)*(b/a)= 1
For any number x:
x 1 = 1 x = x
x/ 1 = x
x 1 = x
1x = 1
X@ 1 = x and 1@x = 1
For any number x, when x is not 0, x0= 1.
As a natural number, 1 is neither a prime number nor a composite number.
square number
Composite number of the first 1 height
Triangular number
Rectangular number
Fibonacci sequence 1 and 2 terms.
1 cannot be used as the radix of the carry system.
1 cannot be the base of logarithm.
The reciprocal of 1 is itself.
In factorial, 0! = 1! = 1
In probability theory, the probability of random events in any sample space is defined as 1.
1 is a positive number, integer, smallest positive integer, odd number, real number, rational number and algebraic number.
In geometry, the radius of the unit circle is 1.
Euler formula establishes the relationship between the five most important constants in mathematics in the simplest way. The formula contains 1 0, the base e of natural logarithm, pi and imaginary unit I of complex number!