NDA2019MathematicsDifferential EquationsActual
Which one of the following is the differential equation that represents the family of curves y= 1 2 x^2-c where c is an arbitrary constant?
Options
- Ad y d x =4 x y^2
- Bd y d x = 1 y
- Cd y d x =x^2 y
- Dd y d x =-4 x y^2
Correct answer
D. d y d x =-4 x y^2
Step-by-step solution
aligned & y= 1 2 x^2-c & d y d x = 0-(4 x) (2 x^2-c )^2 & =-4 x 1 (2 x^2-c )^2 & =-4 x y^2 & d y d x =-4 x y^2 aligned