Metamath Proof Explorer


Theorem tendoi2

Description: Value of additive inverse endomorphism. (Contributed by NM, 12-Jun-2013)

Ref Expression
Hypotheses tendoi.i 𝐼 = ( 𝑠𝐸 ↦ ( 𝑓𝑇 ( 𝑠𝑓 ) ) )
tendoi.t 𝑇 = ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 )
Assertion tendoi2 ( ( 𝑆𝐸𝐹𝑇 ) → ( ( 𝐼𝑆 ) ‘ 𝐹 ) = ( 𝑆𝐹 ) )

Proof

Step Hyp Ref Expression
1 tendoi.i 𝐼 = ( 𝑠𝐸 ↦ ( 𝑓𝑇 ( 𝑠𝑓 ) ) )
2 tendoi.t 𝑇 = ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 )
3 1 2 tendoi ( 𝑆𝐸 → ( 𝐼𝑆 ) = ( 𝑔𝑇 ( 𝑆𝑔 ) ) )
4 3 adantr ( ( 𝑆𝐸𝐹𝑇 ) → ( 𝐼𝑆 ) = ( 𝑔𝑇 ( 𝑆𝑔 ) ) )
5 fveq2 ( 𝑔 = 𝐹 → ( 𝑆𝑔 ) = ( 𝑆𝐹 ) )
6 5 cnveqd ( 𝑔 = 𝐹 ( 𝑆𝑔 ) = ( 𝑆𝐹 ) )
7 6 adantl ( ( ( 𝑆𝐸𝐹𝑇 ) ∧ 𝑔 = 𝐹 ) → ( 𝑆𝑔 ) = ( 𝑆𝐹 ) )
8 simpr ( ( 𝑆𝐸𝐹𝑇 ) → 𝐹𝑇 )
9 fvex ( 𝑆𝐹 ) ∈ V
10 9 cnvex ( 𝑆𝐹 ) ∈ V
11 10 a1i ( ( 𝑆𝐸𝐹𝑇 ) → ( 𝑆𝐹 ) ∈ V )
12 4 7 8 11 fvmptd ( ( 𝑆𝐸𝐹𝑇 ) → ( ( 𝐼𝑆 ) ‘ 𝐹 ) = ( 𝑆𝐹 ) )