Symbols relating to algebra and linear algebra

The following symbols may be used anywhere in text∶
Description
Symbol
Grafstate code
Angle
/_
Right angle
|_
Right triangle
/_|
Parallel
||
Not parallel
!||
Perpendicular
_|_
Not perpendicular
⊥̸
!_|_
Divides
|
Does not divide
!|
Composition
\@
Congruent

==
~=
Not congruent

!==
!~=
Dot product
·
\.
Cross product
\*
Plus or minus
±
+-
Inverse
-1
~1
Infinity
\oo
Rotate counter-clockwise
@`{turn left`}
Rotate clockwise
@`{turn right`}
The vertical bar is used to mean divides in the statement a divides b (written a∣b). The vertical bar may also be used in set notation to separate the subject of a set from its predicate (e.g., {x∣x∈A⋁x∈B}).