Let a unit vector \(\widehat{OP}\) make angles \(\alpha, \beta, \gamma\) with the positive directions of the co-ordinate axes OX, OY, OZ respectively, where \(\beta \in \left(0, \frac{\pi}{2}\right)\). If \(\widehat{OP}\) is perpendicular to the plane through points \((1,2,3), (2,3,4)\) and \((1,5,7)\), then which one of the following is true?