Metamath Proof Explorer

Theorem mulrid

Description: Utility theorem: index-independent form of df-mulr . (Contributed by Mario Carneiro, 8-Jun-2013)

Ref Expression
Assertion mulrid 
|- .r = Slot ( .r ` ndx )

Proof

Step Hyp Ref Expression
1 df-mulr 
 |-  .r = Slot 3
2 3nn 
 |-  3 e. NN
3 1 2 ndxid 
 |-  .r = Slot ( .r ` ndx )