\(P=\dfrac{-2}{\sqrt{x-2}}\)
ĐKXĐ: \(x>2\)
Để P nguyên thì \(2⋮\sqrt{x-2}\)
\(\Rightarrow\sqrt{x-2}\in\left\{-2;-1;1-2\right\}\)
Mà \(\sqrt{x-2}>0\)
\(\Rightarrow\sqrt{x-2}\in\left\{1;2\right\}\)
\(\Rightarrow x-2\in\left\{1;4\right\}\)
\(\Rightarrow x\in\left\{3;6\right\}\)