Home U+2100 to U+214F Letterlike Symbols
Glyph for U+2102
Source: Noto Sans

U+2102 DOUBLE-STRUCK CAPITAL C

U+2102 was added to Unicode in version 1.1 (1993). It belongs to the block U+2100 to U+214F Letterlike Symbols in the U+0000 to U+FFFF Basic Multilingual Plane.

This character is a Uppercase Letter and is commonly used, that is, in no specific script. The character is also known as the set of complex numbers.

The glyph is a Font composition of the glyph Glyph for U+0043 Latin Capital Letter C. It has a Neutral East Asian Width. In bidirectional context it acts as Left To Right and is not mirrored. The glyph can, under circumstances, be confused with 1 other glyphs. In text U+2102 behaves as Alphabetic regarding line breaks. It has type Upper for sentence and Alphabetic Letter for word breaks. The Grapheme Cluster Break is Any.

The Wikipedia has the following information about this codepoint:

In mathematics, a complex number is an element of a number system that extends the real numbers with a specific element denoted i, called the imaginary unit and satisfying the equation i2 = −1; every complex number can be expressed in the form a + bi, where a and b are real numbers. Because no real number satisfies the above equation, i was called an imaginary number by René Descartes. For the complex number a + bi, a is called the real part and b is called the imaginary part. The set of complex numbers is denoted by either of the symbols C {displaystyle mathbb {C} } or C. Despite the historical nomenclature "imaginary", complex numbers are regarded in the mathematical sciences as just as "real" as the real numbers and are fundamental in many aspects of the scientific description of the natural world.

Complex numbers allow solutions to all polynomial equations, even those that have no solutions in real numbers. More precisely, the fundamental theorem of algebra asserts that every non-constant polynomial equation with real or complex coefficients has a solution which is a complex number. For example, the equation ( x + 1 ) 2 = − 9 {displaystyle (x+1)^{2}=-9} has no real solution, since the square of a real number cannot be negative, but has the two nonreal complex solutions −1 + 3i and −1 − 3i.

Addition, subtraction and multiplication of complex numbers can be naturally defined by using the rule i2 = −1 combined with the associative, commutative and distributive laws. Every nonzero complex number has a multiplicative inverse. This makes the complex numbers a field that has the real numbers as a subfield. The complex numbers also form a real vector space of dimension two, with {1, i} as a standard basis.

This standard basis makes the complex numbers a Cartesian plane, called the complex plane. This allows a geometric interpretation of the complex numbers and their operations, and conversely expressing in terms of complex numbers some geometric properties and constructions. For example, the real numbers form the real line which is identified to the horizontal axis of the complex plane. The complex numbers of absolute value one form the unit circle. The addition of a complex number is a translation in the complex plane, and the multiplication by a complex number is a similarity centered at the origin. The complex conjugation is the reflection symmetry with respect to the real axis. The complex absolute value is a Euclidean norm.

In summary, the complex numbers form a rich structure that is simultaneously an algebraically closed field, a commutative algebra over the reals, and a Euclidean vector space of dimension two.

Representations

System Representation
8450
UTF-8 E2 84 82
UTF-16 21 02
UTF-32 00 00 21 02
URL-Quoted %E2%84%82
HTML-Escape ℂ
Wrong windows-1252 Mojibake ℂ
HTML-Escape ℂ
HTML-Escape ℂ
alias the set of complex numbers
LATEX \mathbb{C}

Related Characters

Confusables

Elsewhere

Complete Record

Property Value
Age 1.1 (1993)
Unicode Name DOUBLE-STRUCK CAPITAL C
Unicode 1 Name DOUBLE-STRUCK C
Block Letterlike Symbols
General Category Uppercase Letter
Script Common
Bidirectional Category Left To Right
Combining Class Not Reordered
Decomposition Type Font
Decomposition Mapping Glyph for U+0043 Latin Capital Letter C
Lowercase
Simple Lowercase Mapping Glyph for U+2102 Double-Struck Capital C
Lowercase Mapping Glyph for U+2102 Double-Struck Capital C
Uppercase
Simple Uppercase Mapping Glyph for U+2102 Double-Struck Capital C
Uppercase Mapping Glyph for U+2102 Double-Struck Capital C
Simple Titlecase Mapping Glyph for U+2102 Double-Struck Capital C
Titlecase Mapping Glyph for U+2102 Double-Struck Capital C
Case Folding Glyph for U+2102 Double-Struck Capital C
ASCII Hex Digit
Alphabetic
Bidi Control
Bidi Mirrored
Bidi Paired Bracket Glyph for U+2102 Double-Struck Capital C
Bidi Paired Bracket Type None
Cased
Composition Exclusion
Case Ignorable
Full Composition Exclusion
Changes When Casefolded
Changes When Casemapped
Changes When NFKC Casefolded
Changes When Lowercased
Changes When Titlecased
Changes When Uppercased
Dash
Deprecated
Default Ignorable Code Point
Diacritic
East Asian Width Neutral
Emoji Modifier Base
Emoji Component
Emoji Modifier
Emoji
Emoji Presentation
Extender
Extended Pictographic
FC NFKC Closure Glyph for U+0063 Latin Small Letter C
Grapheme Cluster Break Any
Grapheme Base
Grapheme Extend
Grapheme Link
Hex Digit
Hangul Syllable Type Not Applicable
Hyphen
ID Continue
Ideographic
ID Start
IDS Binary Operator
IDS Trinary Operator and
Indic Mantra Category
Indic Positional Category NA
Indic Syllabic Category Other
ISO 10646 Comment
Joining Group No_Joining_Group
Join Control
Jamo Short Name
Joining Type Non Joining
Line Break Alphabetic
Logical Order Exception
Math
Noncharacter Code Point
NFC Quick Check Yes
NFD Quick Check Yes
NFKC Casefold Glyph for U+0063 Latin Small Letter C
NFKC Quick Check No
NFKD Quick Check No
Numeric Type None
Numeric Value not a number
Other Alphabetic
Other Default Ignorable Code Point
Other Grapheme Extend
Other ID Continue
Other ID Start
Other Lowercase
Other Math
Other Uppercase
Pattern Syntax
Pattern White Space
Prepended Concatenation Mark
Quotation Mark
Radical
Regional Indicator
Sentence Break Upper
Simple Case Folding Glyph for U+2102 Double-Struck Capital C
Script Extension
Soft Dotted
Sentence Terminal
Terminal Punctuation
Unified Ideograph
Vertical Orientation R
Variation Selector
Word Break Alphabetic Letter
White Space
XID Continue
XID Start
Expands On NFC
Expands On NFD
Expands On NFKC
Expands On NFKD