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y^(2)-x^(2) (dy)/(dx) = xy(dy)/(dx)...

` y^(2)-x^(2) (dy)/(dx) = xy(dy)/(dx)`

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To solve the differential equation \( y^2 - x^2 \frac{dy}{dx} = xy \frac{dy}{dx} \), we will follow these steps: ### Step 1: Rearranging the Equation We start with the given equation: \[ y^2 - x^2 \frac{dy}{dx} = xy \frac{dy}{dx} \] We can rearrange this by bringing all terms involving \(\frac{dy}{dx}\) to one side: \[ y^2 = xy \frac{dy}{dx} + x^2 \frac{dy}{dx} \] Factoring out \(\frac{dy}{dx}\): \[ y^2 = \frac{dy}{dx} (xy + x^2) \] ### Step 2: Isolating \(\frac{dy}{dx}\) Now, we isolate \(\frac{dy}{dx}\): \[ \frac{dy}{dx} = \frac{y^2}{xy + x^2} \] ### Step 3: Substituting \(y = ux\) Next, we use the substitution \(y = ux\), where \(u\) is a function of \(x\). Then, we have: \[ \frac{dy}{dx} = u + x \frac{du}{dx} \] Substituting \(y\) and \(\frac{dy}{dx}\) into our equation gives: \[ u + x \frac{du}{dx} = \frac{(ux)^2}{x(ux) + x^2} \] This simplifies to: \[ u + x \frac{du}{dx} = \frac{u^2 x^2}{x^2(u + 1)} \] Canceling \(x^2\) from both sides: \[ u + x \frac{du}{dx} = \frac{u^2}{u + 1} \] ### Step 4: Rearranging for Separation of Variables Rearranging the equation, we get: \[ x \frac{du}{dx} = \frac{u^2}{u + 1} - u \] This simplifies to: \[ x \frac{du}{dx} = \frac{u^2 - u(u + 1)}{u + 1} = \frac{-u}{u + 1} \] ### Step 5: Separating Variables Now we can separate the variables: \[ \frac{(u + 1)}{-u} du = \frac{dx}{x} \] ### Step 6: Integrating Both Sides Integrating both sides: \[ \int \frac{(u + 1)}{-u} du = \int \frac{dx}{x} \] The left side can be split: \[ \int \left(-1 - \frac{1}{u}\right) du = -\ln |x| + C \] This results in: \[ -u - \ln |u| = -\ln |x| + C \] ### Step 7: Substituting Back Since \(u = \frac{y}{x}\), we substitute back: \[ -\frac{y}{x} - \ln \left|\frac{y}{x}\right| = -\ln |x| + C \] This can be rearranged to: \[ \ln |y| + \frac{y}{x} = C + \ln |x| \] ### Final Solution Thus, the general solution of the differential equation is: \[ \ln |y| + \frac{y}{x} = C + \ln |x| \]
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Solve (x^(2)-y^(2))(dy)/(dx)=2xy