Solving homogeneous differential equation $\frac{dy}{dx}=\frac{x^2+8y^2}{3xy}$.

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Solve the differential equation. Use the fact that the given equation is homogeneous $$ \frac{dy}{dx}=\frac{x^2+8y^2}{3xy} $$

First I multiply the right side by $$ \frac{\frac{1}{x^2}}{\frac{1}{x^2}} $$ Then $$\frac{dy}{dx}=\frac{1+\frac{8y^2}{x^2}}{\frac{3y}{x}} $$ $$ Let: v=\frac{y}{x} $$ $$ \frac{dy}{dx}=v+x\frac{dv}{dx} $$ Then substitute $$ \frac{dy}{dx}=\frac{1+v^2}{3v}$$ $$ \frac{1+v^2}{3v}=v+x\frac{dv}{dx}$$

How do I find the solution from here?

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Hint:

First a slight miscalculation (you missed the $8$) on your part, it should be:

$$ \frac{1+8v^2}{3v}=v+x\frac{\mathrm{d}v}{\mathrm{d}x}$$

After this just separate the variables and integrate:

$$\int \frac{\mathrm{d}x}{x}=\int \frac{3v\ \mathrm{d}v}{(1+5v^2)}$$

Can you proceed?

Update:

To help you remove your confusion I have written down the remaining steps:

$$\frac{10}{3}\ln(xc)=\ln\left(1+5\left(\frac{y}{x}\right)^2 \right)$$

$$\ln\left((xc)^{\frac{10}{3}}\right)=\ln\left(1+5\left(\frac{y}{x}\right)^2 \right)$$

$$\frac 15 cx^{\frac{10}{3}}-\frac 15=\frac{y^2}{x^2}$$

$$\frac 15 cx^{\frac{10}{3}} \cdot x^2-\frac {x^2}{5}=y^2$$

$$\implies y=\pm \sqrt{\frac{cx^{\frac{16}{3}}}{5}-\frac {x^2}{5}}$$

$$\implies y=\pm \sqrt{c_1x^{\frac{16}{3}}-\frac {x^2}{5}}$$