COMEDK202510 May 2025Morning ShiftMathematicsDifferential EquationsActual
The solution of the differential equation d y d x +y y x=0 is
Options
- Ax y=c
- Bx y=c
- Cy=c x
- Dy x=c
Correct answer
B. x y=c
Step-by-step solution
The given differential equation is dy dx + y y x = 0 . Rearranging the terms, we get dy y y = - x dx . Integrating both sides, we have dy y y = - x dx . Let u = y , then du = 1 y dy . The integral becomes du u = - x dx . This results in |u| = - | x| + C₁ . Substituting u = y , we get | y| = - | x| + C₁ . This simplifies to | y| + | x| = C₁ , which is | y x| = C₁ . Taking the exponential of both sides, | y x| = e^ C₁ = C . Thus, x y = C . Answer: x y=c