⇒ ⇔ ⇐
Mathematical signs
arithmetic
Plus sign +
Minus sign - , ./.
Mark , ×
Divided sign : , ÷ , /
Plus minus sign ± ,
Comparison sign < , , = , , >
Root sign
Percent sign %
Analysis
Sum symbol Σ
Product mark Π
Difference sign , Nabla ,
Prime
Partial differential
Integral sign
Concatenation characters
Infinity symbol
geometry
Angle sign , , ,
Vertical , parallel ,
Triangle , square ,
Diameter sign
Set theory
Union , cut ,
Difference , complement ,
Element character
Subset , superset , , ,
Empty set
logic
Universal quantifier
Existential quantifier
Conjunction , disjunction ,
Negation sign ¬

The following arrow is a double arrow pointing right, left or both sides. It is the mathematical notation for a logical conclusion .

## use

The following arrow is the mathematical symbol for “it follows,” the logical conclusion . It represents a logical connection : the symbol is used when a correct conclusion is drawn from something right, a wrong conclusion from something wrong, or a right conclusion from something wrong. However, it must never be used to infer something wrong from something right.

x ist durch 4 teilbar ⇒ x ist durch 2 teilbar ⇒ x ist gerade
(here a transitive conclusion , it also follows directly x ist durch 4 teilbar ⇒ x ist gerade)

Of course you can rearrange the conclusions at any time (“follows from”), and then use ⇐ (next arrow on the left). In addition, one can use the arrow ⇔ for mutual conclusions ( equivalence relations ) and say "follows mutually" or "follows equivalently":

4 mal x ist 8 ⇔ 8 durch 4 ist x
Both statements describe the same facts, only formulated differently: They are interchangeable.

If one statement does not follow from another, "does not follow from this" ⇏ is crossed out. Here, too, there is ⇎ "it does not follow equivalent" - but this does not make a statement as to whether the conclusion in one direction is not correct:

x ist durch 4 teilbar ⇎ x ist durch 2 teilbar
with the first example, because one cannot infer from x that x is divisible by 4, but only that it is divisible by 2: The statements “even” and “divisible by 2” are equivalent.

In the various sub-areas and for more precise statements, there are numerous more specific variations of this arrow symbolism.

## Word processing and typesetting

The arrow can also be represented with =>( equal sign and greater than sign ), and is converted in some editors after input.

In Unicode , the mathematical arrows are located in the Unicode block arrows (arrows, 2190–21FF) at the code points:

designation character HEX code
RIGHTWARDS DOUBLE ARROW 0x21d2 U + 21D2
LEFTWARDS DOUBLE ARROW 0x21d0 U + 21D0
LEFT RIGHT DOUBLE ARROW 0x21d4 U + 21D4
RIGHTWARDS DOUBLE ARROW WITH STROKE 0x21d0 U + 21CF
LEFTWARDS DOUBLE ARROW WITH STROKE 0x21d2 U + 21CD
LEFT RIGHT DOUBLE ARROW WITH STROKE 0x21d4 U + 21CE

In addition, there are the same up and down arrows, which can be used in a flowchart-like sentence (in the same block), as well as in an extended form if this is necessary in the sentence (in the Unicode block Additional arrows-A 27F0-27FF)

In TeX they are called \Leftarrow and \Rightarrowand \Leftrightarrow(with a capital in explicit distinction for easy arrow) or \nLeftarrow, \nRightarrow, \nLeftrightarrow(preceded by small ' n' for negation set). There are also several variants here:

syntax Result
\circlearrowleft \circlearrowright ${\ displaystyle \ circlearrowleft \ circlearrowright}$
\curvearrowleft \curvearrowright ${\ displaystyle \ curvearrowleft \ curvearrowright}$
\downarrow \uparrow ${\ displaystyle \ downarrow \ uparrow}$
\downdownarrows \upuparrows ${\ displaystyle \ downdownarrows \ upuparrows}$
\Downarrow \Uparrow ${\ displaystyle \ Downarrow \ Uparrow}$
\hookleftarrow \hookrightarrow ${\ displaystyle \ hookleftarrow \; \ hookrightarrow}$
\leftarrow \rightarrow ${\ displaystyle \ leftarrow \; \ rightarrow}$
\Leftarrow \Rightarrow ${\ displaystyle \ Leftarrow \; \ Rightarrow}$
\leftarrowtail \rightarrowtail ${\ displaystyle \ leftarrowtail \ rightarrowtail}$
\leftharpoondown \rightharpoondown ${\ displaystyle \ leftharpoondown \; \ rightharpoondown}$
\leftharpoonup \rightharpoonup ${\ displaystyle \ leftharpoonup \; \ rightharpoonup}$
\leftleftarrows \rightrightarrows ${\ displaystyle \ leftleftarrows \ rightrightarrows}$
\leftrightarrow \Leftrightarrow ${\ displaystyle \ leftrightarrow \ Leftrightarrow}$
\leftrightarrows \rightleftarrows ${\ displaystyle \ leftrightarrows \ rightleftarrows}$
\leftrightharpoons \rightleftharpoons ${\ displaystyle \ leftrightharpoons \ rightleftharpoons}$
syntax Result
\leftrightsquigarrow \rightsquigarrow ${\ displaystyle \ leftrightsquigarrow \ rightsquigarrow}$
\Lleftarrow \Rrightarrow ${\ displaystyle \ Lleftarrow \ Rrightarrow}$
\longleftarrow \longrightarrow ${\ displaystyle \ longleftarrow \ longrightarrow}$
\Longleftarrow \Longrightarrow ${\ displaystyle \ Longleftarrow \ Longrightarrow}$
\longleftrightarrow ${\ displaystyle \ longleftrightarrow}$
\Longleftrightarrow ${\ displaystyle \ Longleftrightarrow}$
\longmapsto \mapsto ${\ displaystyle \ longmapsto \ mapsto}$
\looparrowleft \looparrowright ${\ displaystyle \ looparrowleft \; \ looparrowright}$
\Lsh \Rsh ${\ displaystyle \ Lsh \; \ Rsh}$
\multimap ${\ displaystyle \ multimap}$
\nearrow \nwarrow \searrow \swarrow ${\ displaystyle \ nearrow \ nwarrow \ searrow \ swarrow}$
\nLeftarrow \nRightarrow ${\ displaystyle \ nLeftarrow \; \ nRightarrow}$
\nleftrightarrow \nLeftrightarrow ${\ displaystyle \ nleftrightarrow \ nLeftrightarrow}$
\restriction ${\ displaystyle \ upharpoonright}$
\twoheadleftarrow \twoheadrightarrow ${\ displaystyle \ twoheadleftarrow \; \ twoheadrightarrow}$
\updownarrow \Updownarrow ${\ displaystyle \ updownarrow \; \ Updownarrow}$