Metamath Proof Explorer


Theorem mulgnncl

Description: Closure of the group multiple (exponentiation) operation for a positive multiplier in a magma. (Contributed by Mario Carneiro, 11-Dec-2014) (Revised by AV, 29-Aug-2021)

Ref Expression
Hypotheses mulgnncl.b
|- B = ( Base ` G )
mulgnncl.t
|- .x. = ( .g ` G )
Assertion mulgnncl
|- ( ( G e. Mgm /\ N e. NN /\ X e. B ) -> ( N .x. X ) e. B )

Proof

Step Hyp Ref Expression
1 mulgnncl.b
 |-  B = ( Base ` G )
2 mulgnncl.t
 |-  .x. = ( .g ` G )
3 eqid
 |-  ( +g ` G ) = ( +g ` G )
4 id
 |-  ( G e. Mgm -> G e. Mgm )
5 ssidd
 |-  ( G e. Mgm -> B C_ B )
6 1 3 mgmcl
 |-  ( ( G e. Mgm /\ x e. B /\ y e. B ) -> ( x ( +g ` G ) y ) e. B )
7 1 2 3 4 5 6 mulgnnsubcl
 |-  ( ( G e. Mgm /\ N e. NN /\ X e. B ) -> ( N .x. X ) e. B )