U+2149 DoubleStruck Italic Small J
U+2149 was added in Unicode version 3.2 in 2002. It belongs to the block
This character is a Lowercase Letter and is commonly used, that is, in no specific script.
The glyph is a font version of the glyph
The Wikipedia has the following information about this codepoint:
The imaginary unit or unit imaginary number (i) is a solution to the quadratic equation x^{2} + 1 = 0. Although there is no real number with this property, i can be used to extend the real numbers to what are called complex numbers, using addition and multiplication. A simple example of the use of i in a complex number is 2 + 3i.
Imaginary numbers are an important mathematical concept; they extend the real number system $R$ to the complex number system $C,$ in which at least one root for every nonconstant polynomial exists (see Algebraic closure and Fundamental theorem of algebra). Here, the term "imaginary" is used because there is no real number having a negative square.
There are two complex square roots of −1: i and −i, just as there are two complex square roots of every real number other than zero (which has one double square root).
In contexts in which use of the letter i is ambiguous or problematic, the letter j is sometimes used instead. For example, in electrical engineering and control systems engineering, the imaginary unit is normally denoted by j instead of i, because i is commonly used to denote electric current.
Representations
System  Representation 

Nº  8521 
UTF8  E2 85 89 
UTF16  21 49 
UTF32  00 00 21 49 
URLQuoted  %E2%85%89 
HTML hex reference  ⅉ 
Wrong windows1252 Mojibake  â…‰ 
Related Characters
Confusables
Elsewhere
Complete Record
Property  Value 

3.2 (2002)  
DOUBLESTRUCK ITALIC SMALL J  
—  
Letterlike Symbols  
Lowercase Letter  
Common  
Left To Right  
Not Reordered  
font  


✔  




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✘  
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✘  
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✘  
✘  
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✘  
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✘  


Any  
✔  
✘  
✘  
✘  
✘  
✔  
✔  
✘  
✘  
0  
0  
0  
✘  
None  
—  
NA  
Other  
—  
✘  
✘  
✔  
✘  
Yes  
Yes  


No  


No  
✘  
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✔  
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✘  
✘  
✘  
Lower  
✔  
✘  
✘  
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✘  
Alphabetic Letter  
✘  
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✘  
✘  
✘  
✘  


None  
neutral  
Not Applicable  
—  
No_Joining_Group  
Non Joining  
Alphabetic  
none  
not a number  


U 