Theorem chub1

Description: Hilbert lattice join is greater than or equal to its first argument. (Contributed by NM, 12-Jun-2004) (New usage is discouraged.)

	Ref	Expression
Assertion	chub1	$$⊢\left(A\in {\mathbf{C}}_{\mathscr{H}}\wedge B\in {\mathbf{C}}_{\mathscr{H}}\right)\to A\subseteq A{\vee }_{\mathscr{H}}B$$

Proof

Step	Hyp	Ref	Expression
1		chsh	$$⊢A\in {\mathbf{C}}_{\mathscr{H}}\to A\in {\mathbf{S}}_{\mathscr{H}}$$
2		chsh	$$⊢B\in {\mathbf{C}}_{\mathscr{H}}\to B\in {\mathbf{S}}_{\mathscr{H}}$$
3		shub1	$$⊢\left(A\in {\mathbf{S}}_{\mathscr{H}}\wedge B\in {\mathbf{S}}_{\mathscr{H}}\right)\to A\subseteq A{\vee }_{\mathscr{H}}B$$
4	1 2 3	syl2an	$$⊢\left(A\in {\mathbf{C}}_{\mathscr{H}}\wedge B\in {\mathbf{C}}_{\mathscr{H}}\right)\to A\subseteq A{\vee }_{\mathscr{H}}B$$