The acute angle between the pair of tangents drawn to the ellipse $2 x^{2}+3 y^{2}=5$ from the point $(1,3)$ is.
$\tan ^{-1}\left(\frac{16}{7 \sqrt{5}}\right)$
$\tan ^{-1}\left(\frac{24}{7 \sqrt{5}}\right)$
$\tan ^{-1}\left(\frac{32}{7 \sqrt{5}}\right)$
$\tan ^{-1}\left(\frac{3+8 \sqrt{5}}{35}\right)$
Let $\frac{x^2}{a^2}+\frac{y^2}{b^2}=1, a>b$ be an ellipse, whose eccentricity is $\frac{1}{\sqrt{2}}$ and the length of the latus rectum is $\sqrt{14}$. Then the square of the eccentricity of $\frac{x^2}{a^2}-\frac{y^2}{b^2}=1$ is :
The eccentricity of the ellipse $4{x^2} + 9{y^2} + 8x + 36y + 4 = 0$ is
The equation of the ellipse whose vertices are $( \pm 5,\;0)$ and foci are $( \pm 4,\;0)$ is
The eccentricity of the ellipse ${\left( {\frac{{x - 3}}{y}} \right)^2} + {\left( {1 - \frac{4}{y}} \right)^2} = \frac{1}{9}$ is
The length of the latus rectum of an ellipse is $\frac{1}{3}$ of the major axis. Its eccentricity is