Metamath Proof Explorer


Theorem mat2pmatvalel

Description: A (matrix) element of the result of a matrix transformation. (Contributed by AV, 31-Jul-2019)

Ref Expression
Hypotheses mat2pmatfval.t 𝑇 = ( 𝑁 matToPolyMat 𝑅 )
mat2pmatfval.a 𝐴 = ( 𝑁 Mat 𝑅 )
mat2pmatfval.b 𝐵 = ( Base ‘ 𝐴 )
mat2pmatfval.p 𝑃 = ( Poly1𝑅 )
mat2pmatfval.s 𝑆 = ( algSc ‘ 𝑃 )
Assertion mat2pmatvalel ( ( ( 𝑁 ∈ Fin ∧ 𝑅𝑉𝑀𝐵 ) ∧ ( 𝑋𝑁𝑌𝑁 ) ) → ( 𝑋 ( 𝑇𝑀 ) 𝑌 ) = ( 𝑆 ‘ ( 𝑋 𝑀 𝑌 ) ) )

Proof

Step Hyp Ref Expression
1 mat2pmatfval.t 𝑇 = ( 𝑁 matToPolyMat 𝑅 )
2 mat2pmatfval.a 𝐴 = ( 𝑁 Mat 𝑅 )
3 mat2pmatfval.b 𝐵 = ( Base ‘ 𝐴 )
4 mat2pmatfval.p 𝑃 = ( Poly1𝑅 )
5 mat2pmatfval.s 𝑆 = ( algSc ‘ 𝑃 )
6 1 2 3 4 5 mat2pmatval ( ( 𝑁 ∈ Fin ∧ 𝑅𝑉𝑀𝐵 ) → ( 𝑇𝑀 ) = ( 𝑥𝑁 , 𝑦𝑁 ↦ ( 𝑆 ‘ ( 𝑥 𝑀 𝑦 ) ) ) )
7 6 adantr ( ( ( 𝑁 ∈ Fin ∧ 𝑅𝑉𝑀𝐵 ) ∧ ( 𝑋𝑁𝑌𝑁 ) ) → ( 𝑇𝑀 ) = ( 𝑥𝑁 , 𝑦𝑁 ↦ ( 𝑆 ‘ ( 𝑥 𝑀 𝑦 ) ) ) )
8 oveq12 ( ( 𝑥 = 𝑋𝑦 = 𝑌 ) → ( 𝑥 𝑀 𝑦 ) = ( 𝑋 𝑀 𝑌 ) )
9 8 fveq2d ( ( 𝑥 = 𝑋𝑦 = 𝑌 ) → ( 𝑆 ‘ ( 𝑥 𝑀 𝑦 ) ) = ( 𝑆 ‘ ( 𝑋 𝑀 𝑌 ) ) )
10 9 adantl ( ( ( ( 𝑁 ∈ Fin ∧ 𝑅𝑉𝑀𝐵 ) ∧ ( 𝑋𝑁𝑌𝑁 ) ) ∧ ( 𝑥 = 𝑋𝑦 = 𝑌 ) ) → ( 𝑆 ‘ ( 𝑥 𝑀 𝑦 ) ) = ( 𝑆 ‘ ( 𝑋 𝑀 𝑌 ) ) )
11 simprl ( ( ( 𝑁 ∈ Fin ∧ 𝑅𝑉𝑀𝐵 ) ∧ ( 𝑋𝑁𝑌𝑁 ) ) → 𝑋𝑁 )
12 simprr ( ( ( 𝑁 ∈ Fin ∧ 𝑅𝑉𝑀𝐵 ) ∧ ( 𝑋𝑁𝑌𝑁 ) ) → 𝑌𝑁 )
13 fvexd ( ( ( 𝑁 ∈ Fin ∧ 𝑅𝑉𝑀𝐵 ) ∧ ( 𝑋𝑁𝑌𝑁 ) ) → ( 𝑆 ‘ ( 𝑋 𝑀 𝑌 ) ) ∈ V )
14 7 10 11 12 13 ovmpod ( ( ( 𝑁 ∈ Fin ∧ 𝑅𝑉𝑀𝐵 ) ∧ ( 𝑋𝑁𝑌𝑁 ) ) → ( 𝑋 ( 𝑇𝑀 ) 𝑌 ) = ( 𝑆 ‘ ( 𝑋 𝑀 𝑌 ) ) )