NTA Abhyas JEE Main2020MathematicsDifferential EquationsPractice
The differential equation of the family of ellipses with centre at the origin and the ends of the major axis being ± 1,0 is of the degree
Options
- A1
- B2
- C3
- D4
Correct answer
A. 1
Step-by-step solution
The general equation of the family is x 2 + y 2 a 2 = 1 … … . . i Differentiating w.r.t. x , we get 2 x + 2 y y ' a 2 = 0 ⇒ x = − y ′ y a 2 ⇒ a 2 = − y ′ x Putting in (i), we have x 2 + y 2 − x y y ′ = 1 or x 2 − x y y ′ = 1 Which is of the degree ‘ 1 ’