Ta có:
\(P=\sqrt{\frac{15}{2}}\cdot\sqrt{\frac{10\left(a-1\right)^2}{3}}\\ =\sqrt{\frac{15}{2}\cdot\frac{10\left(a-1\right)^2}{3}}\\ =\sqrt{25\left(a-1\right)^2}\\ =5\left|a-1\right|\\ =\left[{}\begin{matrix}5\left(a-1\right)\left(a=1\right)\\5\left(1-a\right)\left(a< 1\right)\end{matrix}\right.\\ =\left[{}\begin{matrix}5a-5\\5-5a\end{matrix}\right.\)
P.s: Ko chắc lắm nha :v