# The diagonal triangle

**Geometry**Level pending

Let \(OA\), \(OB\) and \(OC\) be three adjacent edges of a cuboid. Then, which of the following statements could be true.

[1] All the angles in \(\triangle ABC\) are acute.

[2] \(\triangle ABC\) is right-angled.

[3] \(\triangle ABC\) has one obtuse angle in it.