- Exam
- JEE Main
- Year
- 2022
- Date
- 24 June
- Shift
- Morning Shift
- Subject
- Mathematics
- Chapter
- Parabola
JEE Main 2022 · 24 June · Morning Shift · Mathematics · Parabola
If two tangents drawn from a point (α, β) lying on the ellipse 25 x...
Correct answer
0
Step-by-step solution
Let
Equation of tangent to with slope will be
Since the tangent passes through \left(\alpha, \beta\right)\dfrac{1}{2}sin\theta = \dfrac{m}{5}cos\theta + \dfrac{1}{m}⇒ {m}^{2}\left(\dfrac{cos\theta}{5}\right) - m\left(\dfrac{1}{2}sin\theta\right) + 1 = 0m{m}_{1} and {m}_{2}{m}_{1} = 4{m}_{2}{m}_{1} + {m}_{2} = \dfrac{\dfrac{1}{2}sin\theta}{\dfrac{cos\theta}{5}}{m}_{1}{m}_{2} = \dfrac{5}{cos\theta}{m}_{1} and {m}_{2}cos\theta = \dfrac{- 5 \pm \sqrt{29}}{2} ⇒ \cos^{2}\theta = \dfrac{54 \pm 10\sqrt{29}}{4}\alpha = \dfrac{- 5 \pm \sqrt{29}}{10} ⇒ 10\alpha + 5 = \pm \sqrt{29}{\beta}^{2} = \dfrac{1}{4}\sin^{2}\theta ⇒ 16{\beta}^{2} = - 50 \pm 10\sqrt{29}{\left(10\alpha + 5\right)}^{2} + {\left(16{\beta}^{2} + 50\right)}^{2} = 2929$