Variables

a
Transverse axis
b
Conjugate axis
F1(-c,0)
Left focus
F2(c,0)
Right focus
s, t
Asymptotes
e
Eccentricity
1.
Equation of a Hyperbola
$\dfrac{x^2}{a^2}-\dfrac{y^2}{b^2}=1$
2.
$|r_1-r_2| = 2a$
3.
Equations od Asymptotes
$y=\pm\dfrac{b}{a}x$
4.
$c^2=a^2+b^2$
5.
Hyperbola eccentricity
$e=\dfrac{c}{a}$
6.
Equations of directrices
$x=\pm\dfrac{a}{e}$
7.
Parametric equation of the right branch
$\begin{array}{ll} x = a \cosh t \\[1 em] y=b \sinh t \end{array} 0\le t \le 2\pi$
8.
General form of a hyperbola
$Ax^2+Bxy+Cy^2+Dx+Ey+F=0$, where $B^2-4AC > 0 $