The line $x\cos \alpha + y\sin \alpha = p$ will be a tangent to the conic $\frac{{{x^2}}}{{{a^2}}} + \frac{{{y^2}}}{{{b^2}}} = 1$, if

  • A

    ${p^2} = {a^2}{\sin ^2}\alpha + {b^2}{\cos ^2}\alpha $

  • B

    ${p^2} = {a^2} + {b^2}$

  • C

    ${p^2} = {b^2}{\sin ^2}\alpha + {a^2}{\cos ^2}\alpha $

  • D

    None of these

Similar Questions

Let $a , b$ and $\lambda$ be positive real numbers. Suppose $P$ is an end point of the latus rectum of the parabola $y^2=4 \lambda x$, and suppose the ellipse $\frac{x^2}{a^2}+\frac{y^2}{b^2}=1$ passes through the point $P$. If the tangents to the parabola and the ellipse at the point $P$ are perpendicular to each other, then the eccentricity of the ellipse is

  • [IIT 2020]

A tangent is drawn to the ellipse $\frac{{{x^2}}}{{32}} + \frac{{{y^2}}}{8} = 1$ from the point $A(8, 0)$ to touch the ellipse at point $P.$ If the normal at $P$ meets the major axis of ellipse at point $B,$ then the length $BC$ is equal to (where $C$ is centre of ellipse) - ............ $\mathrm{units}$

If the tangent to the parabola $y^2 = x$ at a point $\left( {\alpha ,\beta } \right)\,,\,\left( {\beta  > 0} \right)$ is also a tangent to the ellipse, $x^2 + 2y^2 = 1$, then $a$ is equal to

  • [JEE MAIN 2019]

The foci of the ellipse $25{(x + 1)^2} + 9{(y + 2)^2} = 225$ are at

Eccentricity of the conic $16{x^2} + 7{y^2} = 112$ is