Metamath Proof Explorer


Theorem mat1rhmval

Description: The value of the ring homomorphism F . (Contributed by AV, 22-Dec-2019)

Ref Expression
Hypotheses mat1rhmval.k
|- K = ( Base ` R )
mat1rhmval.a
|- A = ( { E } Mat R )
mat1rhmval.b
|- B = ( Base ` A )
mat1rhmval.o
|- O = <. E , E >.
mat1rhmval.f
|- F = ( x e. K |-> { <. O , x >. } )
Assertion mat1rhmval
|- ( ( R e. Ring /\ E e. V /\ X e. K ) -> ( F ` X ) = { <. O , X >. } )

Proof

Step Hyp Ref Expression
1 mat1rhmval.k
 |-  K = ( Base ` R )
2 mat1rhmval.a
 |-  A = ( { E } Mat R )
3 mat1rhmval.b
 |-  B = ( Base ` A )
4 mat1rhmval.o
 |-  O = <. E , E >.
5 mat1rhmval.f
 |-  F = ( x e. K |-> { <. O , x >. } )
6 opeq2
 |-  ( x = X -> <. O , x >. = <. O , X >. )
7 6 sneqd
 |-  ( x = X -> { <. O , x >. } = { <. O , X >. } )
8 simp3
 |-  ( ( R e. Ring /\ E e. V /\ X e. K ) -> X e. K )
9 snex
 |-  { <. O , X >. } e. _V
10 9 a1i
 |-  ( ( R e. Ring /\ E e. V /\ X e. K ) -> { <. O , X >. } e. _V )
11 5 7 8 10 fvmptd3
 |-  ( ( R e. Ring /\ E e. V /\ X e. K ) -> ( F ` X ) = { <. O , X >. } )