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Solve this homogeneous differential equation to the point dy/dx=y^2+x^2/x^2

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Answer:

Explanation:

To solve the homogeneous differential equation:

dy/dx = (y^2 + x^2)/x^2

We first need to rewrite it in a homogeneous form by dividing both sides by y^2:

dy/dx = (1 + x^2/y^2)/(x^2/y^2)

Let u = y/x, then we can substitute y = ux and dy/dx = u + x(du/dx) into the differential equation to get:

u + x(du/dx) = (1 + u^2)/x^2

Rearranging and separating variables:

x(du/dx) = (1 + u^2 - u)/x

dx/x = (1 - u + u^2)/x * du

Integrating both sides:

ln|x| = ∫(1 - u + u^2)/u du + C

ln|x| = u - 0.5ln|u^2 - u + 1| + C

Substituting back u = y/x:

ln|x| = y/x - 0.5ln|(y/x)^2 - y/x + 1| + C

Simplifying:

ln|x| = y/x - 0.5ln|y^2 - xy + x^2| + C

Exponentiating both sides:

|x| * e^(y/x) = Ce^(-0.5ln|y^2 - xy + x^2|)

|x| * e^(y/x) = C|y^2 - xy + x^2|^-0.5

Squaring both sides and simplifying:

(x^2 + y^2)e^(2y/x) = D

where D = C^2. This is the general solution to the homogeneous differential equation.

answered
User Renato Lochetti
by
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