COMEDK2015MathematicsDifferential Equations
The differential equation of the family of parabolas y²=4 a x , where a is parameter, is
Options
- Ad y d x = y 2 x
- Bd y d x =- y 2 x
- Cd y d x =- 2 y x
- Dd y d x = 2 y x
Correct answer
A. d y d x = y 2 x
Step-by-step solution
Given, equation of parabola is y²=4 a x ...(i) Differentiating E g . (i) w.r.t. x , we get aligned 2 y d y d x &=4 a d y d x &= 2 a y a= y 2 d y d x aligned Substituting the value of a in Eq. (i), we get aligned y² &=4 y 2 d y d x x y² &=2 x y d y d x d y d x = y 2 x aligned