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(x log x ) (dy)/(dx) + y = 2 log x...

` (x log x ) (dy)/(dx) + y = 2 log x `

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To solve the differential equation \((x \log x) \frac{dy}{dx} + y = 2 \log x\), we will follow these steps: ### Step 1: Rewrite the Equation We start by rewriting the equation in standard form: \[ \frac{dy}{dx} + \frac{y}{x \log x} = \frac{2 \log x}{x \log x} \] This simplifies to: \[ \frac{dy}{dx} + \frac{y}{x \log x} = \frac{2}{x} \] ### Step 2: Identify \(p\) and \(q\) From the standard form \(\frac{dy}{dx} + p y = q\), we identify: - \(p = \frac{1}{x \log x}\) - \(q = \frac{2}{x}\) ### Step 3: Find the Integrating Factor The integrating factor \(I\) is given by: \[ I = e^{\int p \, dx} = e^{\int \frac{1}{x \log x} \, dx} \] To solve the integral, we can use the substitution \(t = \log x\), which gives \(dt = \frac{1}{x} dx\) or \(dx = x dt = e^t dt\). Thus, we have: \[ \int \frac{1}{x \log x} \, dx = \int \frac{1}{t} \, dt = \log |t| + C = \log |\log x| + C \] Therefore, the integrating factor is: \[ I = e^{\log |\log x|} = \log x \] ### Step 4: Multiply the Equation by the Integrating Factor Now we multiply the entire differential equation by the integrating factor \(\log x\): \[ \log x \frac{dy}{dx} + \frac{y \log x}{x \log x} = \frac{2 \log x}{x} \] This simplifies to: \[ \log x \frac{dy}{dx} + \frac{y}{x} = \frac{2 \log x}{x} \] ### Step 5: Recognize the Left Side as a Product Derivative The left-hand side can be rewritten as: \[ \frac{d}{dx}(y \log x) = \frac{2 \log x}{x} \] ### Step 6: Integrate Both Sides Integrating both sides with respect to \(x\): \[ \int \frac{d}{dx}(y \log x) \, dx = \int \frac{2 \log x}{x} \, dx \] The left side gives: \[ y \log x = \int \frac{2 \log x}{x} \, dx \] Using integration by parts, let \(u = \log x\) and \(dv = \frac{2}{x} dx\): \[ du = \frac{1}{x} dx, \quad v = 2 \log x \] Thus, we have: \[ \int \frac{2 \log x}{x} \, dx = 2(\log x)^2 + C \] So, \[ y \log x = 2(\log x)^2 + C \] ### Step 7: Solve for \(y\) Finally, we solve for \(y\): \[ y = \frac{2(\log x)^2 + C}{\log x} \] This can be simplified to: \[ y = 2 \log x + \frac{C}{\log x} \] ### Final Solution Thus, the solution to the differential equation is: \[ y = 2 \log x + \frac{C}{\log x} \]

To solve the differential equation \((x \log x) \frac{dy}{dx} + y = 2 \log x\), we will follow these steps: ### Step 1: Rewrite the Equation We start by rewriting the equation in standard form: \[ \frac{dy}{dx} + \frac{y}{x \log x} = \frac{2 \log x}{x \log x} \] This simplifies to: ...
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