Manipal MET2010MathematicsDifferential Equations
If the solution of the differential equation d y d x = a x+3 2 y+f represents a circle, then the value of a is
Options
- A2
- B-2
- C3
- D-4
Correct answer
B. -2
Step-by-step solution
We have, d y d x = a x+3 2 y+f (a x+3) d x=(2 y+f) d y On integrating, we obtain a x^2 2 +3 x=y^2+f y+c - a 2 x^2+y^2-3 x+f y+c=0 This will represent a circle, if - a 2 =1 ( . coefficient of x^2= coefficient of .y^2 ) a=-2