Description: Intersection of a closed subspace and its orthocomplement. Part of Proposition 1 of Kalmbach p. 65. (Contributed by NM, 11-Oct-1999) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | ch0le.1 | |- A e. CH  | 
					|
| Assertion | chocini | |- ( A i^i ( _|_ ` A ) ) = 0H  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | ch0le.1 | |- A e. CH  | 
						|
| 2 | 1 | chshii | |- A e. SH  | 
						
| 3 | ocin | |- ( A e. SH -> ( A i^i ( _|_ ` A ) ) = 0H )  | 
						|
| 4 | 2 3 | ax-mp | |- ( A i^i ( _|_ ` A ) ) = 0H  |