Metamath Proof Explorer


Theorem nmhmco

Description: The composition of bounded linear operators is a bounded linear operator. (Contributed by Mario Carneiro, 20-Oct-2015)

Ref Expression
Assertion nmhmco ( ( 𝐹 ∈ ( 𝑇 NMHom 𝑈 ) ∧ 𝐺 ∈ ( 𝑆 NMHom 𝑇 ) ) → ( 𝐹𝐺 ) ∈ ( 𝑆 NMHom 𝑈 ) )

Proof

Step Hyp Ref Expression
1 nmhmrcl2 ( 𝐹 ∈ ( 𝑇 NMHom 𝑈 ) → 𝑈 ∈ NrmMod )
2 nmhmrcl1 ( 𝐺 ∈ ( 𝑆 NMHom 𝑇 ) → 𝑆 ∈ NrmMod )
3 1 2 anim12ci ( ( 𝐹 ∈ ( 𝑇 NMHom 𝑈 ) ∧ 𝐺 ∈ ( 𝑆 NMHom 𝑇 ) ) → ( 𝑆 ∈ NrmMod ∧ 𝑈 ∈ NrmMod ) )
4 nmhmlmhm ( 𝐹 ∈ ( 𝑇 NMHom 𝑈 ) → 𝐹 ∈ ( 𝑇 LMHom 𝑈 ) )
5 nmhmlmhm ( 𝐺 ∈ ( 𝑆 NMHom 𝑇 ) → 𝐺 ∈ ( 𝑆 LMHom 𝑇 ) )
6 lmhmco ( ( 𝐹 ∈ ( 𝑇 LMHom 𝑈 ) ∧ 𝐺 ∈ ( 𝑆 LMHom 𝑇 ) ) → ( 𝐹𝐺 ) ∈ ( 𝑆 LMHom 𝑈 ) )
7 4 5 6 syl2an ( ( 𝐹 ∈ ( 𝑇 NMHom 𝑈 ) ∧ 𝐺 ∈ ( 𝑆 NMHom 𝑇 ) ) → ( 𝐹𝐺 ) ∈ ( 𝑆 LMHom 𝑈 ) )
8 nmhmnghm ( 𝐹 ∈ ( 𝑇 NMHom 𝑈 ) → 𝐹 ∈ ( 𝑇 NGHom 𝑈 ) )
9 nmhmnghm ( 𝐺 ∈ ( 𝑆 NMHom 𝑇 ) → 𝐺 ∈ ( 𝑆 NGHom 𝑇 ) )
10 nghmco ( ( 𝐹 ∈ ( 𝑇 NGHom 𝑈 ) ∧ 𝐺 ∈ ( 𝑆 NGHom 𝑇 ) ) → ( 𝐹𝐺 ) ∈ ( 𝑆 NGHom 𝑈 ) )
11 8 9 10 syl2an ( ( 𝐹 ∈ ( 𝑇 NMHom 𝑈 ) ∧ 𝐺 ∈ ( 𝑆 NMHom 𝑇 ) ) → ( 𝐹𝐺 ) ∈ ( 𝑆 NGHom 𝑈 ) )
12 7 11 jca ( ( 𝐹 ∈ ( 𝑇 NMHom 𝑈 ) ∧ 𝐺 ∈ ( 𝑆 NMHom 𝑇 ) ) → ( ( 𝐹𝐺 ) ∈ ( 𝑆 LMHom 𝑈 ) ∧ ( 𝐹𝐺 ) ∈ ( 𝑆 NGHom 𝑈 ) ) )
13 isnmhm ( ( 𝐹𝐺 ) ∈ ( 𝑆 NMHom 𝑈 ) ↔ ( ( 𝑆 ∈ NrmMod ∧ 𝑈 ∈ NrmMod ) ∧ ( ( 𝐹𝐺 ) ∈ ( 𝑆 LMHom 𝑈 ) ∧ ( 𝐹𝐺 ) ∈ ( 𝑆 NGHom 𝑈 ) ) ) )
14 3 12 13 sylanbrc ( ( 𝐹 ∈ ( 𝑇 NMHom 𝑈 ) ∧ 𝐺 ∈ ( 𝑆 NMHom 𝑇 ) ) → ( 𝐹𝐺 ) ∈ ( 𝑆 NMHom 𝑈 ) )