Metamath Proof Explorer


Theorem tendo02

Description: Value of additive identity endomorphism. (Contributed by NM, 11-Jun-2013)

Ref Expression
Hypotheses tendo0cbv.o 𝑂 = ( 𝑓𝑇 ↦ ( I ↾ 𝐵 ) )
tendo02.b 𝐵 = ( Base ‘ 𝐾 )
Assertion tendo02 ( 𝐹𝑇 → ( 𝑂𝐹 ) = ( I ↾ 𝐵 ) )

Proof

Step Hyp Ref Expression
1 tendo0cbv.o 𝑂 = ( 𝑓𝑇 ↦ ( I ↾ 𝐵 ) )
2 tendo02.b 𝐵 = ( Base ‘ 𝐾 )
3 eqidd ( 𝑔 = 𝐹 → ( I ↾ 𝐵 ) = ( I ↾ 𝐵 ) )
4 1 tendo0cbv 𝑂 = ( 𝑔𝑇 ↦ ( I ↾ 𝐵 ) )
5 funi Fun I
6 2 fvexi 𝐵 ∈ V
7 resfunexg ( ( Fun I ∧ 𝐵 ∈ V ) → ( I ↾ 𝐵 ) ∈ V )
8 5 6 7 mp2an ( I ↾ 𝐵 ) ∈ V
9 3 4 8 fvmpt ( 𝐹𝑇 → ( 𝑂𝐹 ) = ( I ↾ 𝐵 ) )