Which of the following transformations reduce the

 differential equation  $\frac{dz}{dx}+\frac{z}{x}\log z=\frac{z}{x^2}(\log z{)}^2$into the form 

$\frac{du}{dx}+P\left(x\right)u=Q\left(x\right)$

we have, 

$\frac{1}{z(\log z{)}^2}\frac{dz}{dx}+\frac{1}{x}\times \frac{1}{\log z}=\frac{1}{x^2}$

Putting $\frac{1}{\log z}=u$and $-\frac{1}{z(\log z{)}^2}\frac{dz}{dx}=\frac{du}{dx}$, we get 

$-\frac{du}{dx}+\frac{u}{x}=\frac{1}{x^2}$ 

$\Rightarrow \frac{du}{dx}+\left(-\frac{1}{x}\right)u=-\frac{1}{x^2}$ or , $\frac{du}{dx}+P\left(x\right)u=Q\left(x\right),$

$P\left(x\right)=-\frac{1}{x}$and $Q\left(x\right)=-\frac{1}{x^2}$