Description: A subspace sum contains a member of one of its subspaces. (Contributed by NM, 19-Oct-1999) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | shincl.1 | |- A e. SH  | 
					|
| shincl.2 | |- B e. SH  | 
					||
| Assertion | shsel1i | |- ( C e. A -> C e. ( A +H B ) )  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | shincl.1 | |- A e. SH  | 
						|
| 2 | shincl.2 | |- B e. SH  | 
						|
| 3 | shsel1 | |- ( ( A e. SH /\ B e. SH ) -> ( C e. A -> C e. ( A +H B ) ) )  | 
						|
| 4 | 1 2 3 | mp2an | |- ( C e. A -> C e. ( A +H B ) )  |