Metamath Proof Explorer


Theorem 0blo

Description: The zero operator is a bounded linear operator. (Contributed by NM, 8-Dec-2007) (New usage is discouraged.)

Ref Expression
Hypotheses 0blo.0 𝑍 = ( 𝑈 0op 𝑊 )
0blo.7 𝐵 = ( 𝑈 BLnOp 𝑊 )
Assertion 0blo ( ( 𝑈 ∈ NrmCVec ∧ 𝑊 ∈ NrmCVec ) → 𝑍𝐵 )

Proof

Step Hyp Ref Expression
1 0blo.0 𝑍 = ( 𝑈 0op 𝑊 )
2 0blo.7 𝐵 = ( 𝑈 BLnOp 𝑊 )
3 eqid ( 𝑈 LnOp 𝑊 ) = ( 𝑈 LnOp 𝑊 )
4 1 3 0lno ( ( 𝑈 ∈ NrmCVec ∧ 𝑊 ∈ NrmCVec ) → 𝑍 ∈ ( 𝑈 LnOp 𝑊 ) )
5 eqid ( 𝑈 normOpOLD 𝑊 ) = ( 𝑈 normOpOLD 𝑊 )
6 5 1 nmoo0 ( ( 𝑈 ∈ NrmCVec ∧ 𝑊 ∈ NrmCVec ) → ( ( 𝑈 normOpOLD 𝑊 ) ‘ 𝑍 ) = 0 )
7 0re 0 ∈ ℝ
8 6 7 eqeltrdi ( ( 𝑈 ∈ NrmCVec ∧ 𝑊 ∈ NrmCVec ) → ( ( 𝑈 normOpOLD 𝑊 ) ‘ 𝑍 ) ∈ ℝ )
9 5 3 2 isblo2 ( ( 𝑈 ∈ NrmCVec ∧ 𝑊 ∈ NrmCVec ) → ( 𝑍𝐵 ↔ ( 𝑍 ∈ ( 𝑈 LnOp 𝑊 ) ∧ ( ( 𝑈 normOpOLD 𝑊 ) ‘ 𝑍 ) ∈ ℝ ) ) )
10 4 8 9 mpbir2and ( ( 𝑈 ∈ NrmCVec ∧ 𝑊 ∈ NrmCVec ) → 𝑍𝐵 )