If the tangent on the point $(2\sec \phi ,\;3\tan \phi )$ of the hyperbola $\frac{{{x^2}}}{4} - \frac{{{y^2}}}{9} = 1$ is parallel to $3x - y + 4 = 0$, then the value of $\phi$ is ............ $^o$
$45$
$60$
$30$
$75$
Locus of foot of normal drawn from any focus to variable tangent of hyperbola $4x^2-9y^2-8x- 18y = 41$ will be
The equation of the hyperbola whose conjugate axis is $5$ and the distance between the foci is $13$, is
The length of transverse axis of the parabola $3{x^2} - 4{y^2} = 32$ is
The locus of the point of instruction of the lines $\sqrt 3 x - y - 4 \sqrt 3 t = 0$ $\&$ $\sqrt 3tx + ty - 4\sqrt 3 = 0$ (where $ t$ is a parameter) is a hyperbola whose eccentricity is
Centre of hyperbola $9{x^2} - 16{y^2} + 18x + 32y - 151 = 0$ is