4.
已知向量\(\vec{m}=\left( \sqrt{3}{\sin }x,{\sin }x \right),\vec{n}=\left( {\cos }x,{\sin }x \right)\).
\((1)\)若\(\vec{m}/\!/\vec{n}\)且\(x\in \left[ 0,\dfrac{\pi }{2} \right]\),求角\(x\);
\((2)\)若\(f(x)=\overset{\to }{{m}}\,\bullet \overset{\to }{{n}}\,\),求函数\(f\left( x \right)\)的最小正周期和单调递增区间.