Metamath Proof Explorer


Theorem rrgss

Description: Left-regular elements are a subset of the base set. (Contributed by Stefan O'Rear, 22-Mar-2015)

Ref Expression
Hypotheses rrgss.e E = RLReg R
rrgss.b B = Base R
Assertion rrgss E B

Proof

Step Hyp Ref Expression
1 rrgss.e E = RLReg R
2 rrgss.b B = Base R
3 eqid R = R
4 eqid 0 R = 0 R
5 1 2 3 4 rrgval E = x B | y B x R y = 0 R y = 0 R
6 5 ssrab3 E B