Metamath Proof Explorer


Theorem trlcocnv

Description: Swap the arguments of the trace of a composition with converse. (Contributed by NM, 1-Jul-2013)

Ref Expression
Hypotheses trlcocnv.h 𝐻 = ( LHyp ‘ 𝐾 )
trlcocnv.t 𝑇 = ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 )
trlcocnv.r 𝑅 = ( ( trL ‘ 𝐾 ) ‘ 𝑊 )
Assertion trlcocnv ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇𝐺𝑇 ) → ( 𝑅 ‘ ( 𝐹 𝐺 ) ) = ( 𝑅 ‘ ( 𝐺 𝐹 ) ) )

Proof

Step Hyp Ref Expression
1 trlcocnv.h 𝐻 = ( LHyp ‘ 𝐾 )
2 trlcocnv.t 𝑇 = ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 )
3 trlcocnv.r 𝑅 = ( ( trL ‘ 𝐾 ) ‘ 𝑊 )
4 cnvco ( 𝐹 𝐺 ) = ( 𝐺 𝐹 )
5 cocnvcnv1 ( 𝐺 𝐹 ) = ( 𝐺 𝐹 )
6 4 5 eqtri ( 𝐹 𝐺 ) = ( 𝐺 𝐹 )
7 6 fveq2i ( 𝑅 ( 𝐹 𝐺 ) ) = ( 𝑅 ‘ ( 𝐺 𝐹 ) )
8 simp1 ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇𝐺𝑇 ) → ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) )
9 1 2 ltrncnv ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐺𝑇 ) → 𝐺𝑇 )
10 9 3adant2 ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇𝐺𝑇 ) → 𝐺𝑇 )
11 1 2 ltrnco ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇 𝐺𝑇 ) → ( 𝐹 𝐺 ) ∈ 𝑇 )
12 10 11 syld3an3 ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇𝐺𝑇 ) → ( 𝐹 𝐺 ) ∈ 𝑇 )
13 1 2 3 trlcnv ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ ( 𝐹 𝐺 ) ∈ 𝑇 ) → ( 𝑅 ( 𝐹 𝐺 ) ) = ( 𝑅 ‘ ( 𝐹 𝐺 ) ) )
14 8 12 13 syl2anc ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇𝐺𝑇 ) → ( 𝑅 ( 𝐹 𝐺 ) ) = ( 𝑅 ‘ ( 𝐹 𝐺 ) ) )
15 7 14 syl5reqr ( ( ( 𝐾 ∈ HL ∧ 𝑊𝐻 ) ∧ 𝐹𝑇𝐺𝑇 ) → ( 𝑅 ‘ ( 𝐹 𝐺 ) ) = ( 𝑅 ‘ ( 𝐺 𝐹 ) ) )