Metamath Proof Explorer


Theorem dfpprod2

Description: Expanded definition of parallel product. (Contributed by Scott Fenton, 3-May-2014)

Ref Expression
Assertion dfpprod2 ⊢ pprod A B = 1 st ↾ V × V -1 ∘ A ∘ 1 st ↾ V × V ∩ 2 nd ↾ V × V -1 ∘ B ∘ 2 nd ↾ V × V

Proof

Step Hyp Ref Expression
1 df-pprod ⊢ pprod A B = A ∘ 1 st ↾ V × V ⊗ B ∘ 2 nd ↾ V × V
2 df-txp ⊢ A ∘ 1 st ↾ V × V ⊗ B ∘ 2 nd ↾ V × V = 1 st ↾ V × V -1 ∘ A ∘ 1 st ↾ V × V ∩ 2 nd ↾ V × V -1 ∘ B ∘ 2 nd ↾ V × V
3 1 2 eqtri ⊢ pprod A B = 1 st ↾ V × V -1 ∘ A ∘ 1 st ↾ V × V ∩ 2 nd ↾ V × V -1 ∘ B ∘ 2 nd ↾ V × V