The first case is an example of “bent four in the corner” (or rather a shape that can be reduced to one), where White is dead. See the Sensei’s Library article Bent four in the corner is dead at Sensei's Library
See also: [Study Group] Essential Life and Death Patterns - #13 by yebellz
The second shape is a seki, assuming that the White group is surrounded and cannot make another eye elsewhere.