Metamath Proof Explorer


Theorem lmhmlin

Description: A homomorphism of left modules is K -linear. (Contributed by Stefan O'Rear, 1-Jan-2015)

Ref Expression
Hypotheses lmhmlin.k 𝐾 = ( Scalar ‘ 𝑆 )
lmhmlin.b 𝐵 = ( Base ‘ 𝐾 )
lmhmlin.e 𝐸 = ( Base ‘ 𝑆 )
lmhmlin.m · = ( ·𝑠𝑆 )
lmhmlin.n × = ( ·𝑠𝑇 )
Assertion lmhmlin ( ( 𝐹 ∈ ( 𝑆 LMHom 𝑇 ) ∧ 𝑋𝐵𝑌𝐸 ) → ( 𝐹 ‘ ( 𝑋 · 𝑌 ) ) = ( 𝑋 × ( 𝐹𝑌 ) ) )

Proof

Step Hyp Ref Expression
1 lmhmlin.k 𝐾 = ( Scalar ‘ 𝑆 )
2 lmhmlin.b 𝐵 = ( Base ‘ 𝐾 )
3 lmhmlin.e 𝐸 = ( Base ‘ 𝑆 )
4 lmhmlin.m · = ( ·𝑠𝑆 )
5 lmhmlin.n × = ( ·𝑠𝑇 )
6 eqid ( Scalar ‘ 𝑇 ) = ( Scalar ‘ 𝑇 )
7 1 6 2 3 4 5 islmhm ( 𝐹 ∈ ( 𝑆 LMHom 𝑇 ) ↔ ( ( 𝑆 ∈ LMod ∧ 𝑇 ∈ LMod ) ∧ ( 𝐹 ∈ ( 𝑆 GrpHom 𝑇 ) ∧ ( Scalar ‘ 𝑇 ) = 𝐾 ∧ ∀ 𝑎𝐵𝑏𝐸 ( 𝐹 ‘ ( 𝑎 · 𝑏 ) ) = ( 𝑎 × ( 𝐹𝑏 ) ) ) ) )
8 7 simprbi ( 𝐹 ∈ ( 𝑆 LMHom 𝑇 ) → ( 𝐹 ∈ ( 𝑆 GrpHom 𝑇 ) ∧ ( Scalar ‘ 𝑇 ) = 𝐾 ∧ ∀ 𝑎𝐵𝑏𝐸 ( 𝐹 ‘ ( 𝑎 · 𝑏 ) ) = ( 𝑎 × ( 𝐹𝑏 ) ) ) )
9 8 simp3d ( 𝐹 ∈ ( 𝑆 LMHom 𝑇 ) → ∀ 𝑎𝐵𝑏𝐸 ( 𝐹 ‘ ( 𝑎 · 𝑏 ) ) = ( 𝑎 × ( 𝐹𝑏 ) ) )
10 fvoveq1 ( 𝑎 = 𝑋 → ( 𝐹 ‘ ( 𝑎 · 𝑏 ) ) = ( 𝐹 ‘ ( 𝑋 · 𝑏 ) ) )
11 oveq1 ( 𝑎 = 𝑋 → ( 𝑎 × ( 𝐹𝑏 ) ) = ( 𝑋 × ( 𝐹𝑏 ) ) )
12 10 11 eqeq12d ( 𝑎 = 𝑋 → ( ( 𝐹 ‘ ( 𝑎 · 𝑏 ) ) = ( 𝑎 × ( 𝐹𝑏 ) ) ↔ ( 𝐹 ‘ ( 𝑋 · 𝑏 ) ) = ( 𝑋 × ( 𝐹𝑏 ) ) ) )
13 oveq2 ( 𝑏 = 𝑌 → ( 𝑋 · 𝑏 ) = ( 𝑋 · 𝑌 ) )
14 13 fveq2d ( 𝑏 = 𝑌 → ( 𝐹 ‘ ( 𝑋 · 𝑏 ) ) = ( 𝐹 ‘ ( 𝑋 · 𝑌 ) ) )
15 fveq2 ( 𝑏 = 𝑌 → ( 𝐹𝑏 ) = ( 𝐹𝑌 ) )
16 15 oveq2d ( 𝑏 = 𝑌 → ( 𝑋 × ( 𝐹𝑏 ) ) = ( 𝑋 × ( 𝐹𝑌 ) ) )
17 14 16 eqeq12d ( 𝑏 = 𝑌 → ( ( 𝐹 ‘ ( 𝑋 · 𝑏 ) ) = ( 𝑋 × ( 𝐹𝑏 ) ) ↔ ( 𝐹 ‘ ( 𝑋 · 𝑌 ) ) = ( 𝑋 × ( 𝐹𝑌 ) ) ) )
18 12 17 rspc2v ( ( 𝑋𝐵𝑌𝐸 ) → ( ∀ 𝑎𝐵𝑏𝐸 ( 𝐹 ‘ ( 𝑎 · 𝑏 ) ) = ( 𝑎 × ( 𝐹𝑏 ) ) → ( 𝐹 ‘ ( 𝑋 · 𝑌 ) ) = ( 𝑋 × ( 𝐹𝑌 ) ) ) )
19 9 18 syl5com ( 𝐹 ∈ ( 𝑆 LMHom 𝑇 ) → ( ( 𝑋𝐵𝑌𝐸 ) → ( 𝐹 ‘ ( 𝑋 · 𝑌 ) ) = ( 𝑋 × ( 𝐹𝑌 ) ) ) )
20 19 3impib ( ( 𝐹 ∈ ( 𝑆 LMHom 𝑇 ) ∧ 𝑋𝐵𝑌𝐸 ) → ( 𝐹 ‘ ( 𝑋 · 𝑌 ) ) = ( 𝑋 × ( 𝐹𝑌 ) ) )