Question about Samsung Ue49ku6400

Yes, that is possible.

Yes, I did that too. However, I had mounted a Vogels bracket that can be swivelled. This makes it easier to mount.

Yes, this is possible. You need a wall mount that supports the VESA wall mount type 400 x 400 mm.

By the way, Samsung recommends the following product for wall mounting: Samsung WMN550M/XC, Mini Wall Mount 32"-65" (Wall)