Solve the d.e $(x+\sqrt{y^2-xy})dy-ydx=0$

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So this is a homogeneous differential equation. I use the substitution $y=ux$, $dy=udx+xdu$ And after simplification, got this integral: $$ \int\frac{1+\sqrt{u^2-u}}{u\sqrt{u^2-u}}du $$ I broke it up into two fractions, cancelling out the $\sqrt{u^2-u}$ in one to get, after integration, $\log|u|$ and the other one I have is $$\int \frac{1}{u\sqrt{u^2-u}}du$$

After completing the square I got $$ \int\frac{1}{u\sqrt{(u-\frac{1}{2})^2-\frac{1}{4}}}du $$ This looks like an arcsec trick but I'm not quite sure how to manipulate it to get it into the correct format.

Any tips? Is this the right approach?

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Hint

$$\frac{1 + \sqrt{u^2-u}}{u\cdot\sqrt{u^2 - u}} = \frac{1}{u\cdot \sqrt{u^2-u}} + \frac{1}{u}$$

Once you split into this, you'll have two integrals. The second one is trivial, it will be a log.

The first one can be evaluated by completing the square inside the root as:

$$u \sqrt{\left(u - \frac{1}{2}\right)^2 - \frac{u}{4}}$$

and then make a suitable substitution.

Can you proceed?

Hint 2

At this point, use a suitable substitution like

$$y = u - \frac{1}{2}$$

$$\int\frac{1}{\left(y + \frac{1}{2}\right)\sqrt{y^2 - \frac{1}{4}}}\ \text{d}y$$

Now a cute substitution to take may be

$$y = \frac{\sec(z)}{2} ~~~~~~~~~~~ \text{d}y = \frac{1}{2}\tan(z)\sec(z)\ \text{d}z$$

Can you proceed?

Hint 3

After the substitution, and after having arranged the integral, you'll get

$$\frac{1}{2}\int \frac{2\sec(z)}{\frac{\sec(z)}{2} + \frac{1}{2}}\ \text{d}z$$

simplify the $2$ and then another non standard substitution will help:

$$k = \tan\left(\frac{z}{2}\right) ~~~~~~~~~~~ \text{d}k = \frac{1}{2}\sec^2\left(\frac{z}{2}\right)\ \text{d}z$$

Can you proceed?

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Put $u=\frac{1}{t}$ in the integral ($\int \frac{du}{u\sqrt{u^2-u}}$) To get (after simplification) $$ \int \frac{-dt}{\sqrt{1-t}}$$ Which evaluates to $$2\sqrt{1-t}+C$$ $$=\color{red}{2\sqrt {\frac{u-1}{u}}+C}$$

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Take out $u$ again, and then take $1-\frac{1}{u} = t$, then $\frac{du}{u^2} = dt$.

There you go.