12.1: Table of Symbols

$( )$	Parentheses (grouping symbols)
$[ ]$	Brackets (grouping symbols)
$\{ \}$	Braces (grouping symbols)
$=$	equal
$\not =$	not equal to
$\approx$	approximately equal to
$>$	greater than
$<$	less than
$≥$	greater than or equal to
$≤$	less than or equal to
$x$	variable or constant
$-x$	negative of $x$ (opposite of $x$)
$|x|$	absolute value of $x$
$\dfrac{1}{x}$	reciprocal of $x$
$(a, b)$	ordered pair with component $a$ and second component $b$
$\pi$	the irrational number pi, often approximated by $3.14$
$\sqrt{a}$	the principal square root of $a$
$-\sqrt{a}$	the secondary square root of $a$