The differential equation whose solution is $A x^2+B y^2=1$, where A and B are arbitrary constants, is of
Answer & explanation
Correct answer: option 4
We have,
$A x^2+B y^2=1$ .....(i)
Differentiating w.r. to $x$, we get
$2 A x+2 B y \frac{d y}{d x}=0 \Rightarrow A x+B y \frac{d y}{d x}=0$ .......(ii)
Differentiating w.r. to $x$, we get
$A+B\left(\frac{d y}{d x}\right)^2+B y \frac{d^2 y}{d x^2}=0$ .....(iii)
Multiplying (iii) by $x$ and subtracting (ii) from it, we get
$x\left(\frac{d y}{d x}\right)^2+x y \frac{d^2 y}{d x^2}-y \frac{d y}{d x}=0$
Clearly, it is a second order and first degree differential equation.