9.
\((1)\)已知\(a\),\(b\),\(c\)分别是\(\triangle ABC\)的三个内角\(A\),\(B\),\(C\)的对边,若\(a=1\),\(b=\sqrt{3}\),\(A+C=2B\),则\(\sin C=\)________.
\((2)\)若实数\(x\),\(y\)满足不等式组\(\begin{cases} & x+3y-3\geqslant 0 \\ & 2x-y-3\leqslant 0 \\ & x-y+1\geqslant 0 \\ \end{cases}\)则\(x+y\)的最大值为________.
\((3)\)若\(|\overrightarrow{a}|=1\),\(|\overrightarrow{b}|=2\),\(\overrightarrow{c}=\overrightarrow{a}+\overrightarrow{b}\),且\(\overrightarrow{a}\bot \overrightarrow{c}\),则向量\(\overrightarrow{a}\)与\(\overrightarrow{b}\)的夹角为________.
\((4)\)观察下列各式:
\(a+b=1\),\(a^{2}+b^{2}=3\),\(a^{3}+b^{3}=4\),\(a^{4}+b^{4}=7\),\(a^{5}+b^{5}=11\),\(……\),则\(a^{10}+b^{10}=\)