2.
已知定义在区间\((0,+∞)\)上的函数\(f(x)\)满足\(f\left( \dfrac{x_{1}}{x_{2}} \right)=f(x_{1})-f(x_{2})\),且当\(x > 1\)时,\(f(x) > 0\),\(f(3)=1\).
\((1)\)判断\(f(x)\)的单调性\(;\)
\((2)\)解关于\(x\)的不等式\(f(3x+6)+f\left( \dfrac{1}{x} \right) > 2;\)
\((3)\)若\(f(x)\leqslant m^{2}-2am+1\)对所有\(x∈(0,3]\),\(a∈[-1,1]\)恒成立,求实数\(m\)的取值范围.