Metamath Proof Explorer


Theorem ofc1

Description: Left operation by a constant. (Contributed by Mario Carneiro, 24-Jul-2014)

Ref Expression
Hypotheses ofc1.1
|- ( ph -> A e. V )
ofc1.2
|- ( ph -> B e. W )
ofc1.3
|- ( ph -> F Fn A )
ofc1.4
|- ( ( ph /\ X e. A ) -> ( F ` X ) = C )
Assertion ofc1
|- ( ( ph /\ X e. A ) -> ( ( ( A X. { B } ) oF R F ) ` X ) = ( B R C ) )

Proof

Step Hyp Ref Expression
1 ofc1.1
 |-  ( ph -> A e. V )
2 ofc1.2
 |-  ( ph -> B e. W )
3 ofc1.3
 |-  ( ph -> F Fn A )
4 ofc1.4
 |-  ( ( ph /\ X e. A ) -> ( F ` X ) = C )
5 fnconstg
 |-  ( B e. W -> ( A X. { B } ) Fn A )
6 2 5 syl
 |-  ( ph -> ( A X. { B } ) Fn A )
7 inidm
 |-  ( A i^i A ) = A
8 fvconst2g
 |-  ( ( B e. W /\ X e. A ) -> ( ( A X. { B } ) ` X ) = B )
9 2 8 sylan
 |-  ( ( ph /\ X e. A ) -> ( ( A X. { B } ) ` X ) = B )
10 6 3 1 1 7 9 4 ofval
 |-  ( ( ph /\ X e. A ) -> ( ( ( A X. { B } ) oF R F ) ` X ) = ( B R C ) )