Follow arrow
⇒ ⇔ ⇐
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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 | |
Follow arrow | ⇒ , ⇔ , ⇐ |
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
)
- (here a transitive conclusion , it also follows directly
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 \Rightarrow
and \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:
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See also
Individual evidence
- ↑ List of mathematical symbols. mathe-online.at, accessed on March 3, 2012 .