The first one looks like it was routed or done with a shaper.
The second looks like formed solid surface material. Possibly shaped with a shaper or router.
The third appears to be a mitered return.
The first would be easy to accomplish with a large round over bit. Depending on the thickness of the material, you'd want the radius to match.
'The true soldier fights not because he hates what is in front of him, but because he loves what is behind him.' G. K. Chesterton
Please edit your profile with a name and location so we can better assist you and make for a friendlier forum.