If $a$ and $c$ are positive real numbers and the ellipse $\frac{{{x^2}}}{{4{c^2}}} + \frac{{{y^2}}}{{{c^2}}} = 1$ has four distinct points in common with the circle $x^2 + y^2 = 9a^2$ , then
$9ac -9a^2 - 2c^2 <0$
$6ac + 9a^2 - 2c^2 < 0$
$9ac -9a^2 -2c^2 > 0$
$6ac +9a^2 - 2c^2 >0$
The equation of tangent and normal at point $(3, -2)$ of ellipse $4{x^2} + 9{y^2} = 36$ are
Find the coordinates of the foci, the vertices, the lengths of major and minor axes and the eccentricity of the ellipse $9 x^{2}+4 y^{2}=36$.
The eccentricity of the ellipse $9{x^2} + 5{y^2} - 30y = 0$, is
If $ \tan\ \theta _1. tan \theta _2 $ $= -\frac{{{a^2}}}{{{b^2}}}$ then the chord joining two points $\theta _1 \& \theta _2$ on the ellipse $\frac{{{x^2}}}{{{a^2}}} + \frac{{{y^2}}}{{{b^2}}}$ $= 1$ will subtend a right angle at :
In an ellipse $9{x^2} + 5{y^2} = 45$, the distance between the foci is