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Solution of the differential equation ...

Solution of the differential equation
`x(dy)/(dx) +2y = x^(2) log x ` is Then
`x^(2)-y^(2)-1+cx=0`. True or False

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To solve the differential equation \( x \frac{dy}{dx} + 2y = x^2 \log x \) and verify if the solution can be expressed as \( x^2 - y^2 - 1 + cx = 0 \), we will follow these steps: ### Step 1: Rewrite the Differential Equation We start with the given equation: \[ x \frac{dy}{dx} + 2y = x^2 \log x \] We can divide the entire equation by \( x \) to simplify it: \[ \frac{dy}{dx} + \frac{2y}{x} = x \log x \] ### Step 2: Identify \( p \) and \( q \) The equation is now in the standard form of a linear differential equation: \[ \frac{dy}{dx} + p y = q \] where \( p = \frac{2}{x} \) and \( q = x \log x \). ### Step 3: Find the Integrating Factor The integrating factor \( \mu(x) \) is given by: \[ \mu(x) = e^{\int p \, dx} = e^{\int \frac{2}{x} \, dx} = e^{2 \log x} = x^2 \] ### Step 4: Multiply the Equation by the Integrating Factor Now, we multiply the entire differential equation by the integrating factor \( x^2 \): \[ x^2 \frac{dy}{dx} + 2xy = x^3 \log x \] ### Step 5: Rewrite the Left-Hand Side The left-hand side can be rewritten as the derivative of a product: \[ \frac{d}{dx}(x^2 y) = x^3 \log x \] ### Step 6: Integrate Both Sides Now, we integrate both sides: \[ \int \frac{d}{dx}(x^2 y) \, dx = \int x^3 \log x \, dx \] The left-hand side simplifies to: \[ x^2 y = \int x^3 \log x \, dx \] To solve the right-hand side, we use integration by parts. Let: - \( u = \log x \) and \( dv = x^3 dx \) Then: - \( du = \frac{1}{x} dx \) and \( v = \frac{x^4}{4} \) Using integration by parts: \[ \int x^3 \log x \, dx = \frac{x^4}{4} \log x - \int \frac{x^4}{4} \cdot \frac{1}{x} \, dx = \frac{x^4}{4} \log x - \frac{1}{4} \int x^3 \, dx \] Calculating the remaining integral: \[ \int x^3 \, dx = \frac{x^4}{4} \] Thus: \[ \int x^3 \log x \, dx = \frac{x^4}{4} \log x - \frac{x^4}{16} + C \] ### Step 7: Solve for \( y \) Now substituting back, we have: \[ x^2 y = \frac{x^4}{4} \log x - \frac{x^4}{16} + C \] Dividing by \( x^2 \): \[ y = \frac{x^2}{4} \log x - \frac{x^2}{16} + \frac{C}{x^2} \] ### Step 8: Compare with the Given Solution The given solution is: \[ x^2 - y^2 - 1 + cx = 0 \] We can see that the derived solution does not match the form provided in the statement. Therefore, the statement is **False**. ### Conclusion The solution of the differential equation \( x \frac{dy}{dx} + 2y = x^2 \log x \) does not yield the expression \( x^2 - y^2 - 1 + cx = 0 \).
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