\(P=\dfrac{\sqrt{a}}{a\sqrt{a}-3a+3\sqrt{a}+1}\) \(\left(a\ge0\right)\)
\(=\dfrac{\sqrt{a}}{\left(\sqrt{a}-1\right)^3-1}\)
Ta có: \(\left\{{}\begin{matrix}\sqrt{a}\ge0\\\left(\sqrt{a}-1\right)^3-1\ge-2\end{matrix}\right.\)
\(\Rightarrow P\le0\)
\(MaxP=0\Leftrightarrow a=0\)