Metamath Proof Explorer


Theorem ssrind

Description: Add right intersection to subclass relation. (Contributed by Glauco Siliprandi, 2-Jan-2022)

Ref Expression
Hypothesis ssrind.1 φ A B
Assertion ssrind φ A C B C

Proof

Step Hyp Ref Expression
1 ssrind.1 φ A B
2 ssrin A B A C B C
3 1 2 syl φ A C B C