\((1)\)在直角坐标系\(xOy\)中,直线\(l\)的方程是\(x+2y-1=0\),圆\(C\)的参数方程是\(\begin{cases} & x=3+3\cos \varphi \\ & y=3\sin \varphi \end{cases}(φ\)为参数\()\),以\(O\)为极点,\(x\)轴的非负半轴为极轴建立极坐标系.
\(①\)求直线\(l\)和圆\(C\)的极坐标方程;
\(②\)已知射线\(OM︰θ=α(\)其中\(0 < \alpha < \dfrac{\pi }{2})\)与圆\(C\)交于\(O\),\(P\)两点,射线\(OQ:\theta =\alpha +\dfrac{\pi }{2}\)与直线\(l\)交于\(Q\)点,若\(|OP|·|OQ|=6\),求\(α\)的值.
\((2)\)已知函数\(f(x)=|2x-a|+8x\),\(x > -2\),\(a > 0\).
\(①\)当\(a=1\)时\(.\)求不等式\(f(x)\geqslant 2x+1\)的解集;
\(②\)若函数\(g(x)=f(x)-7x-a^{2}+3\)的图象落在区域\(\begin{cases} & x > -2, \\ & y\geqslant 0 \end{cases}\)内,求实数\(a\)的取值范围.