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Binary Operators Relations

Basic binary symbols can be produced by typing the correspoding keyboard character. These include

 + - = < >

A general expressions can be input in the natural manner. For example $x+y$ gives

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Notice that TeX took care of the spacing around +. Mathematicians use a lot of symbols that are not avialable on the keyboard.

TeX (and ConTeXt) provide macros to input them. For example $x \times y$ gives

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The following is a partial list of frequently used binary operators and relations.

Commonly Used Binary Operators Commonly used relation symbols Set Relations
\pm
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\leq
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\subset
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\mp
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\ll
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\subseteq
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\times
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\geq
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\supset
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\div
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\gg
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\supseteq
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\ast
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\equiv
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\cap
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\star
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\sim
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\cup
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\bullet
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\simeq
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\in
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\circ
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\approx
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\cdot
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\neq
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Sums, products, integrals

Sums with \sum

  • \setupbodyfont[14pt]
    \framed[frame=off,align=normal]{%
     \m{\sum_{k = 0}^{j + n} a_k = e^{a + b - c}}  \blank[small]
    \dm{\sum_{k = 0}^{j + n} a_k = e^{a + b - c}}}
    
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Products with \prod

  • \setupbodyfont[14pt]
    \framed[frame=off,align=normal]{%
     \m{\prod_{i=a}^{b} f(i)}  \blank[small]
    \dm{\prod_{i=a}^{b} f(i)}}
    
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Integrals with \int

  • \setupbodyfont[14pt]
    \framed[frame=off,align=normal]{%
     \m{\int_a^b f(x) \dd x }  \blank[small]      
    \dm{\int_a^b f(x) \dd x }  \blank[small]
    
    \setupmathematics[differentiald=upright]
    \dm{\int_a^b f(x) \dd x }  \blank[small]               
    }
    
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Greek Letters

To type the greek character α you can say $\alpha$ which gives

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. If you have a utf enabled keyboard, you can also type the α directly and ConTeXt will correctly interpret it. For example,

\enableregime[utf]

Here is some Greek math $α^2 + β^2 = γ^2$

Here is a complete list of greek letters

lowercase greek letters variation uppercase greek letters
\alpha
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\beta
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\gamma
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\Gamma
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\delta
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\Delta
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\epsilon
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\varepsilon
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\zeta
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\eta
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\theta
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\vartheta
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\Theta
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\iota
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\kappa
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\lambda
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\Lambda
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\mu
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\nu
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\xi
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\Xi
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\omicron
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\pi
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\varpi
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\Pi
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\rho
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\varrho
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\sigma
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\varsigma
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\Sigma
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\tau
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\upsilon
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\Upsilon
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\phi
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\Phi
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\chi
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\psi
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\Psi
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\omega
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\Omega
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Subscript and superscript

TeX uses ^ and _ to denote superscripts and subscripts. It is perhaps easiest to explain this by means of some examples.

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is written as $x_{10}^{15}$ or $x^{15}_{10}$. The order in which _ and ^ are given does not matter. One can also type complicated expressions like

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as $a_{b_{c_{d_{e}}}}$.


To align superscripts and subscripts one after the other (not above/below each other), you can either add empty sub- and superscripts or use the command \noscript between indices. (See Section 2.7 in the Mathematics in ConTeXt manual (https://www.pragma-ade.com/general/manuals/mathincontext-screen.pdf).) $T^a_{}_b^{}^c = T^a \noscript _b \noscript^c$ gives:

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List of All Math macros

With \usemodule[fnt-25], \showmathfontcharacters produces a lengthy annotated catalogue. Here is the first page:

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In ConTeXt MkII, you can see the list of all math macros by \showmathcharacters.


Spacing

TeX handles math spacing by breaking a formula into parts, and assigning each of those parts a role such as 'Ord' (a variable or number) or 'Rel' (equality, larger than, et cetera). For each combination of roles, it then looks up the spacing appropriate between them in a table. These are the roles:

Ord e.g. 4 or a or x2
Op Unary operators such as sin or ln.
Bin Binary operators such as '+'
Rel Relationships such as '=' or '>' or '\implies'
Open open brackets of any kind
Close closing brackets of any kind
Punct Punctuation: digit separators like '.' or ','.
Inner Fractions are inner. What else is inner?

To set up e.g. the spacing between ordinal items, do as follows (since dec 2012):

 \startsetups math:morespacing
     \ordordspacing\textstyle 1mu plus .5mu minus .25mu\relax
 \stopsetups

 \setupmathematics
   [setups=math:morespacing]