Differential Equations · JEE Main previous year questions

2004 2 questions

1. Q342004 · 24 Apr 2004 · Shift 1

   Solution of the differential equation $ydx+(x+x^{2}y)dy=0$ is

   1. A.$\log y=Cx$
   2. B.$-\frac{1}{xy}+\log y=C$
   3. C.$\frac{1}{xy}+\log y=C$
   4. D.$-\frac{1}{xy}=C$
   Show answer

   Answer: B

2. Q642004 · 24 Apr 2004 · Shift 1

   The differential equation for the family of circle $x^2+y^2-2ay=0$, where a is an arbitrary constant is :

   1. A.$(x^2+y^2)y^{\prime }=2xy$
   2. B.$2(x^2+y^2)y^{\prime }=xy$
   3. C.$(x^2-y^2)y^{\prime }=2xy$
   4. D.$2(x^2-y^2)y^{\prime }=xy$
   Show answer

   Answer: C