NTA Abhyas JEE Main2020MathematicsEllipsePractice
If the tangent to the ellipse x 2 + 4 y 2 = 16 at P 4 cos θ , 2 sin θ is also a normal to the circle x 2 + y 2 = 8 x + 4 y , then the sum of all possible values of θ is equal to ∀ θ ∈ 0 , 2 π
Options
- Aπ 2
- Bπ 4
- C5 π 2
- D7 π 4
Correct answer
A. π 2
Step-by-step solution
Tangent to the ellipse is x cos θ + 2 y sin θ = 4 which is a normal to the given circle ⇒ it satisfies 4 , 2 ⇒ sin θ + cos θ = 1 ∴ θ = 0 , π 2