10.
\((1)\)点\(P(2,1)\)关于直线\(x-y+1=0\)的对称点\(Q\)的坐标为_______________.
\((2)\)已知\(\triangle ABC\)的一个内角为\(120^{\circ}\),且三边长构成公差为\(2\)的等差数列,则\(\triangle ABC\)的面积为____________.
\((3)\)已知\(\left\{{a}_{n}\right\} \)是公比为\(q\)的等比数列,\({{S}_{n}}\)是\(\left\{{a}_{n}\right\} \)的前\(n\)项和,且\(9{{S}_{3}}={{S}_{6}}\),若正数\(a,b\)满足:\(\dfrac{2}{a}+\dfrac{4}{b}=q\),则\(\dfrac{2}{a-1}+\dfrac{1}{b-2}\)的最小值为___________.
\((4)\)已知函数\(f(x)=\ln \dfrac{1+x}{1-x}+\sin x\),则关于\(a\)的不等式\(f(a-2)+f({{a}^{2}}-4) < 0\)的解集是_________.