Modern Arabic mathematical notation explained

Modern Arabic mathematical notation is a mathematical notation based on the Arabic script, used especially at pre-university levels of education. Its form is mostly derived from Western notation, but has some notable features that set it apart from its Western counterpart. The most remarkable of those features is the fact that it is written from right to left following the normal direction of the Arabic script. Other differences include the replacement of the Greek and Latin alphabet letters for symbols with Arabic letters and the use of Arabic names for functions and relations.

Features

Variations

Notation differs slightly from one region to another. In tertiary education, most regions use the Western notation. The notation mainly differs in numeral system used, and in mathematical symbols used.

Numeral systems

There are three numeral systems used in right to left mathematical notation.

European
(descended from Western Arabic)
49
Arabic-Indic (Eastern Arabic)<-- U+0660 thru U+0669 -->Arabic: ٠|italic=no Arabic: ١|italic=no Arabic: ٢|italic=no Arabic: ٣|italic=no Arabic: ٤|italic=noArabic: ٥|italic=no Arabic: ٦|italic=no Arabic: ٧|italic=no Arabic: ٨|italic=no Arabic: ٩|italic=no
Perso-Arabic variant<-- U+06F0 thru U+06F9 -->Persian: ۰|italic=no Persian: ۱|italic=no Persian: ۲|italic=no Persian: ۳|italic=no Persian: ۴|italic=noPersian: ۵|italic=no Persian: ۶|italic=no Persian: ۷|italic=no Persian: ۸|italic=no Persian: ۹|italic=no
Urdu variant
Written numerals are arranged with their lowest-value digit to the right, with higher value positions added to the left. That is identical to the arrangement used by Western texts using Hindu-Arabic numerals even though Arabic script is read from right to left. The symbols "٫" and "٬" may be used as the decimal mark and the thousands separator respectively when writing with Eastern Arabic numerals, e.g. Arabic: ٣٫١٤١٥٩٢٦٥٣٥٨ 3.14159265358, Arabic: ١٬٠٠٠٬٠٠٠٬٠٠٠ 1,000,000,000. Negative signs are written to the left of magnitudes, e.g. Arabic: ٣− −3. In-line fractions are written with the numerator and denominator on the left and right of the fraction slash respectively, e.g. Arabic: ٢/٧ 2/7.

Symbols

Sometimes, symbols used in Arabic mathematical notation differ according to the region:

Sometimes, mirrored Latin and Greek symbols are used in Arabic mathematical notation (especially in western Arabic regions):

However, in Iran, usually Latin and Greek symbols are used.

Examples

Mathematical letters

LatinArabicNotes

a

From the Arabic letter Arabic: ا ʾalif; a and Arabic: ا ʾalif are the first letters of the Latin alphabet and the Arabic alphabet's ʾabjadī sequence respectively, and the letters also share a common ancestor and the same sound

b

A dotless Arabic: ب bāʾ; b and Arabic: ب bāʾ are the second letters of the Latin alphabet and the ʾabjadī sequence respectively

c

From the initial form of Arabic: ح ḥāʾ, or that of a dotless Arabic: ج jīm; c and Arabic: ج jīm are the third letters of the Latin alphabet and the ʾabjadī sequence respectively, and the letters also share a common ancestor and the same sound

d

From the Arabic letter Arabic: د dāl; d and Arabic: د dāl are the fourth letters of the Latin alphabet and the ʾabjadī sequence respectively, and the letters also share a common ancestor and the same sound

x

From the Arabic letter Arabic: س sīn. It is contested that the usage of Latin x in maths is derived from the first letter Arabic: ش šīn (without its dots) of the Arabic word Arabic: شيء šayʾ(un) pronounced as /ar/, meaning thing.[1] (X was used in old Spanish for the sound /ʃ/). However, according to others there is no historical evidence for this.[2] [3]

y

From the Arabic letter Arabic: ص ṣād

z

From the Arabic letter Arabic: ع ʿayn

Mathematical constants and units

DescriptionLatinArabicNotes
Euler's number

e

Initial form of the Arabic letter Arabic: ه hāʾ. Both Latin letter e and Arabic letter Arabic: ه hāʾ are descendants of Phoenician letter .
imaginary unit

i

From Arabic: ت tāʾ, which is in turn derived from the first letter of the second word of Arabic: وحدة تخيلية waḥdaẗun taḫīliyya "imaginary unit"
pi

\pi

From Arabic: ط ṭāʾ; also

\pi

in some regions
radius

r

From Arabic: ن nūn followed by a dotless Arabic: ق qāf, which is in turn derived from Arabic: نصف القطر nuṣfu l-quṭr "radius"
kilogramkgFrom Arabic: كجم kāf-jīm-mīm. In some regions alternative symbols like (kāf-ġayn) or (kāf-lām-ġayn) are used. All three abbreviations are derived from Arabic: كيلوغرام kīlūġrām "kilogram" and its variant spellings.
gramgFrom Arabic: جم jīm-mīm, which is in turn derived from Arabic: جرام jrām, a variant spelling of Arabic: غرام ġrām "gram"
metremFrom Arabic: م mīm, which is in turn derived from Arabic: متر mitr "metre"
centimetrecmFrom Arabic: سم sīn-mīm, which is in turn derived from Arabic: سنتيمتر "centimetre"
millimetremmFrom Arabic: مم mīm-mīm, which is in turn derived from Arabic: مليمتر millīmitr "millimetre"
kilometrekmFrom Arabic: كم kāf-mīm; also (kāf-lām-mīm) in some regions; both are derived from Arabic: كيلومتر kīlūmitr "kilometre".
secondsFrom Arabic: ث ṯāʾ, which is in turn derived from Arabic: ثانية ṯāniya "second"
minuteminFrom Arabic: د dālʾ, which is in turn derived from Arabic: دقيقة daqīqa "minute"; also (i.e. dotless Arabic: ق qāf) in some regions
hourhFrom Arabic: س sīnʾ, which is in turn derived from Arabic: ساعة sāʿa "hour"
kilometre per hourkm/hFrom the symbols for kilometre and hour
degree Celsius°CFrom Arabic: س sīn, which is in turn derived from the second word of Arabic: درجة سيلسيوس darajat sīlsīūs "degree Celsius"; also from Arabic: م mīmʾ, which is in turn derived from the first letter of the third word of Arabic: درجة حرارة مئوية "degree centigrade"
degree Fahrenheit°FFrom Arabic: ف fāʾ, which is in turn derived from the second word of Arabic: درجة فهرنهايت darajat fahranhāyt "degree Fahrenheit"
millimetres of mercurymmHgFrom Arabic: مم&zwnj;ز mīm-mīm zayn, which is in turn derived from the initial letters of the words Arabic: مليمتر زئبق "millimetres of mercury"
ÅngströmÅFrom Arabic: أْ ʾalif with hamzah and ring above, which is in turn derived from the first letter of "Ångström", variously spelled Arabic: أنغستروم or Arabic: أنجستروم

Sets and number systems

DescriptionLatinArabicNotes
Natural numbers

N

From Arabic: ط ṭāʾ, which is in turn derived from the first letter of the second word of Arabic: عدد طبيعي ʿadadun ṭabīʿiyyun "natural number"
Integers

Z

From Arabic: ص ṣād, which is in turn derived from the first letter of the second word of Arabic: عدد صحيح ʿadadun ṣaḥīḥun "integer"
Rational numbers

Q

From Arabic: ن nūn, which is in turn derived from the first letter of Arabic: نسبة nisba "ratio"
Real numbers

R

From Arabic: ح ḥāʾ, which is in turn derived from the first letter of the second word of Arabic: عدد حقيقي ʿadadun ḥaqīqiyyun "real number"
Imaginary numbers

I

From Arabic: ت tāʾ, which is in turn derived from the first letter of the second word of Arabic: عدد تخيلي ʿadadun taḫīliyyun "imaginary number"
Complex numbers

C

From Arabic: م mīm, which is in turn derived from the first letter of the second word of Arabic: عدد مركب ʿadadun murakkabun "complex number"
Empty set

\varnothing

\varnothing

Is an element of

\in

\ni

A mirrored ∈
Subset

\subset

\supset

A mirrored ⊂
Superset

\supset

\subset

A mirrored ⊃
Universal set

S

From Arabic: ش šīn, which is in turn derived from the first letter of the second word of Arabic: مجموعة شاملة majmūʿatun šāmila "universal set"

Arithmetic and algebra

DescriptionLatin/GreekArabicNotes
Percent%e.g. 100% "Arabic: ٪١٠٠ "
Permille is an Arabic equivalent of the per ten thousand sign ‱.
Is proportional to

\propto

A mirrored ∝
n th root

\sqrt[n]{}

Arabic: ں is a dotless Arabic: ن nūn while is a mirrored radical sign √
Logarithm

log

From Arabic: لو lām-wāw, which is in turn derived from لوغاريتم "logarithm"
Logarithm to base b

logb

Natural logarithm

ln

From the symbols of logarithm and Euler's number
Summation

\sum

Arabic: مجـــ mīm-medial form of jīm is derived from the first two letters of Arabic: مجموع majmūʿ "sum"; also (, a mirrored summation sign ∑) in some regions
Product

\prod

From Arabic: جذ jīm-ḏāl. The Arabic word for "product" is جداء jadāʾun. Also

\prod

in some regions.
Factorial

n!

Also in some regions
Permutations
nP
r
Also is used in some regions as

P(n,r)

Combinations
nC
k
Also is used in some regions as

C(n,k)

and as the binomial coefficient

n\choosek

Trigonometric and hyperbolic functions

Trigonometric functions

DescriptionLatinArabicNotes
Sine

\sin

from Arabic: حاء ḥāʾ (i.e. dotless Arabic: ج jīm)-ʾalif; also (jīm-bāʾ) is used in some regions (e.g. Syria); Arabic for "sine" is Arabic: جيب jayb
Cosine

\cos

from Arabic: حتا ḥāʾ (i.e. dotless Arabic: ج jīm)-tāʾ-ʾalif; also (tāʾ-jīm-bāʾ) is used in some regions (e.g. Syria); Arabic for "cosine" is Arabic: جيب تمام
Tangent

\tan

from Arabic: طا ṭāʾ (i.e. dotless Arabic: ظ ẓāʾ)-ʾalif; also (ẓāʾ-lām) is used in some regions (e.g. Syria); Arabic for "tangent" is Arabic: ظل ẓill
Cotangent

\cot

from Arabic: طتا ṭāʾ (i.e. dotless Arabic: ظ ẓāʾ)-tāʾ-ʾalif; also (tāʾ-ẓāʾ-lām) is used in some regions (e.g. Syria); Arabic for "cotangent" is Arabic: ظل تمام
Secant

\sec

from Arabic: ٯا dotless Arabic: ق qāf-ʾalif; Arabic for "secant" is Arabic: قاطع
Cosecant

\csc

from Arabic: ٯتا dotless Arabic: ق qāf-tāʾ-ʾalif; Arabic for "cosecant" is Arabic: قاطع تمام

Hyperbolic functions

The letter (zayn, from the first letter of the second word of Arabic: دالة زائدية "hyperbolic function") is added to the end of trigonometric functions to express hyperbolic functions. This is similar to the way

\operatorname{h}

is added to the end of trigonometric functions in Latin-based notation.
DescriptionHyperbolic sineHyperbolic cosineHyperbolic tangentHyperbolic cotangentHyperbolic secantHyperbolic cosecant
Latin

\sinh

\cosh

\tanh

\coth

\operatorname{sech}

\operatorname{csch}

Arabic

Inverse trigonometric functions

For inverse trigonometric functions, the superscript in Arabic notation is similar in usage to the superscript

-1

in Latin-based notation.
DescriptionInverse sineInverse cosineInverse tangentInverse cotangentInverse secantInverse cosecant
Latin

\sin-1

\cos-1

\tan-1

\cot-1

\sec-1

\csc-1

Arabic

Inverse hyperbolic functions

DescriptionInverse hyperbolic sineInverse hyperbolic cosineInverse hyperbolic tangentInverse hyperbolic cotangentInverse hyperbolic secantInverse hyperbolic cosecant
Latin

\sinh-1

\cosh-1

\tanh-1

\coth-1

\operatorname{sech}-1

\operatorname{csch}-1

Arabic

Calculus

DescriptionLatinArabicNotes
Limit

\lim

Arabic: نهــــا nūn-hāʾ-ʾalif is derived from the first three letters of Arabic Arabic: نهاية nihāya "limit"
Function

f(x)

Arabic: د dāl is derived from the first letter of Arabic: دالة "function". Also called Arabic: تابع, Arabic: تا for short, in some regions.
Derivatives

f'(x),\dfrac{dy}{dx},\dfrac{d2y}{dx2},\dfrac{\partial{y}}{\partial{x}}

‵ is a mirrored prime ′ while ، is an Arabic comma. The signs should be mirrored: .
Integrals

\int{},\iint{},\iiint{},\oint{}

&#x202a; ، ، ،&#x202c;Mirrored ∫, ∬, ∭ and ∮

Complex analysis

See also

External links

Notes and References

  1. Web site: Moore. Terry. Why is X the Unknown. Ted Talk. 2012-10-11. 2014-02-22. https://web.archive.org/web/20140222163108/http://www.ted.com/talks/terry_moore_why_is_x_the_unknown.html. dead.
  2. Book: Cajori, Florian. A History of Mathematical Notation. 1993. registration. Courier Dover Publications. 11 October 2012. 382–383. 9780486677668. Nor is there historical evidence to support the statement found in Noah Webster's Dictionary, under the letter x, to the effect that 'x was used as an abbreviation of Ar. shei (a thing), something, which, in the Middle Ages, was used to designate the unknown, and was then prevailingly transcribed as xei.'.
  3. Book: Oxford Dictionary, 2nd Edition. There is no evidence in support of the hypothesis that x is derived ultimately from the mediaeval transliteration xei of shei "thing", used by the Arabs to denote the unknown quantity, or from the compendium for L. res "thing" or radix "root" (resembling a loosely-written x), used by mediaeval mathematicians..