2025 ACJC P2 Q1

It is given that \(\overrightarrow{OA} = 3\mathbf{i} + \mathbf{j} + 3\mathbf{k}\) and \(\overrightarrow{OB} = 5\mathbf{i} - 4\mathbf{j} + 3\mathbf{k}\). Find the position vector of a point \(R\) on line \(OB\) such that \(AR\) is perpendicular to \(OB\). Hence find the position vector of the point \(A'\), the reflection of the point \(A\) in the line \(OB\).[4]