2.
在平面直角坐标系\(xOy\)中,曲线\(C\)的参数方程为\(\begin{cases} & x=3\cos \alpha \\ & y=\sin \alpha \end{cases}\) \((\)\(\alpha \)为参数\()\),在以原点为极点,\(x\)轴正半轴为极轴的极坐标系中,直线\(l\)的极坐标方程为\(\rho \sin \left( \theta -\dfrac{\pi }{4} \right)=\sqrt{2}\).
\((1)\)求\(C\)的普通方程和直线\(l\)的倾斜角;
\((2)\)设点\(P\left( 0,2 \right),l\)和\(C\)交于\(A,B\)两点,求\(\left| PA \right|+\left| PB \right|\).