Best way to check one little flat face lies inside another big flat face

Hi guys, is it possible to check that one small flat face with free-form boundaries lies on a large face with free-form boundaries? Well, i need to check:

1) whether the small FACE2 lies on the plane of the large FACE1.

2) whether the small FACE2 doesn't go beyond the boundaries of the large FACE1, that is, i need to check that the small FACE2 lies entirely within the boundaries of the large FACE1.

P.S.: FACE2 has no same domain with FACE1 or something else, it's just simple external face that is not connected to FACE1 in any way.

Maybe BRepClass3d_SolidClassifier? But i think, it's not so good idea, maybe there is a much more elegant and simple way?

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