24. 已知函数f(x)=log3(x2−1)f(x)={\log _3}({{x^2}-1})f(x)=log3(x2−1)，g(x)=x2−2x+ag(x)=x^{2}-2x+ag(x)=x2−2x+a，∃x1∈[2\exist x_{1}\in [2∃x1∈[2，+∞)+\infty )+∞)，∀x2∈[13,3]\forall {x_2}\in [{\frac{1}{3},3}]∀x2∈[31,3]有f(x1)⩽g(x2)f(x_{1})\leqslant g(x_{2})f(x1)⩽g(x2)，则实数aaa的取值范围是 ___{a∣a⩾2}\{a\vert a\geqslant 2\}{a∣a⩾2}___．