First order non-linear ODE with quadratic and linear derivatives

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I have the following ODE and I am not sure how to solve it. I have manipulated it a bit, but am not sure if my approach is the correct thing to do.

$$ 0 = z^c-2(c-1)[1-z]y(z) + [2(1-z)-\mu]y'(z)-[\mu y']^2 $$

Dividing by $\mu^2$ to isolate the quadratic term

$$ 0 = \frac{z^c}{\mu^2}-\frac{2(c-1)}{\mu^2}[1-z]y(z) + \frac{1}{\mu^2}[2(1-z)-\mu]y'(z)-(y')^2 $$

Letting

$$ \alpha(z) = \frac{1}{\mu^2}[2(1-z)-\mu] $$

and

$$ \beta(z) = \frac{2(c-1)}{\mu^2}[1-z] $$

This becomes

$$ 0 = \frac{z^c}{\mu^2}-\beta y(z) + \alpha y'(z)-(y')^2 $$

or

$$ (y')^2 - \alpha y'(z) +\beta y(z) -\frac{z^c}{\mu^2}= 0 $$

However, I am not sure that it is acceptable to wrap the $1-z$ terms away into $\alpha$ and $\beta$.

If it is acceptable, then I will take the following square root of my expression

$$ y' = \pm \sqrt{\alpha y' -\beta y +\frac{z^c}{\mu}} $$

This is not separable, so I don't think I can integrate it directly. Additionally, I am concerned about the "hidden" $1-z$ terms wrapped into $\alpha$ and $\beta$.