The equation of a curve passing through the origin and satisfying the different equation $ \frac{dy}{dx} = (x-y)^2 ,$ is |
$e^{2x}(1- x+y) = 1+ x- y$ $e^{2x}(1+ x-y) = 1- x+ y$ $e^{2x}(1-x+y) + (1+ x-y) = 0 $ $e^{2x} (1+ x+y) = 1- x+ y$ |
$e^{2x}(1- x+y) = 1+ x- y$ |
The correct answer is option (1) : $e^{2x}(1- x+y) = 1+ x- y$ We have, $\frac{dy}{dx} = (x- y)^2 $ Let $x-y = v .$ Then, $1-\frac{dy}{dx} =\frac{dv}{dx}$ $⇒\frac{dy}{dx} = 1-\frac{dv}{dx}$ $∴\frac{dy}{dx} = (x-y)^2 $ $⇒1-\frac{dv}{dx} = v^2$ $⇒1-v^2 = \frac{dv}{dx}$ $⇒dx=\frac{1}{1-v^2 }dv$ $⇒2∫dx= 2∫\frac{1}{1-v^2 }dv$ $⇒2x=log \left(\frac{1+v}{1-v} \right) + kog C$ $⇒C \left(\frac{1+v}{1-v} \right) = e^{2x}$ $⇒C\left(\frac{x-y+1}{y-x+1}\right) =e^{2x}$ $⇒C(x-y+1) = e^{2x} (y-x+1)$ |