Metamath Proof Explorer


Theorem opsqrlem3

Description: Lemma for opsqri . (Contributed by NM, 22-Aug-2006) (New usage is discouraged.)

Ref Expression
Hypotheses opsqrlem2.1 𝑇 ∈ HrmOp
opsqrlem2.2 𝑆 = ( 𝑥 ∈ HrmOp , 𝑦 ∈ HrmOp ↦ ( 𝑥 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑥𝑥 ) ) ) ) )
opsqrlem2.3 𝐹 = seq 1 ( 𝑆 , ( ℕ × { 0hop } ) )
Assertion opsqrlem3 ( ( 𝐺 ∈ HrmOp ∧ 𝐻 ∈ HrmOp ) → ( 𝐺 𝑆 𝐻 ) = ( 𝐺 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝐺𝐺 ) ) ) ) )

Proof

Step Hyp Ref Expression
1 opsqrlem2.1 𝑇 ∈ HrmOp
2 opsqrlem2.2 𝑆 = ( 𝑥 ∈ HrmOp , 𝑦 ∈ HrmOp ↦ ( 𝑥 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑥𝑥 ) ) ) ) )
3 opsqrlem2.3 𝐹 = seq 1 ( 𝑆 , ( ℕ × { 0hop } ) )
4 id ( 𝑧 = 𝐺𝑧 = 𝐺 )
5 4 4 coeq12d ( 𝑧 = 𝐺 → ( 𝑧𝑧 ) = ( 𝐺𝐺 ) )
6 5 oveq2d ( 𝑧 = 𝐺 → ( 𝑇op ( 𝑧𝑧 ) ) = ( 𝑇op ( 𝐺𝐺 ) ) )
7 6 oveq2d ( 𝑧 = 𝐺 → ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑧𝑧 ) ) ) = ( ( 1 / 2 ) ·op ( 𝑇op ( 𝐺𝐺 ) ) ) )
8 4 7 oveq12d ( 𝑧 = 𝐺 → ( 𝑧 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑧𝑧 ) ) ) ) = ( 𝐺 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝐺𝐺 ) ) ) ) )
9 eqidd ( 𝑤 = 𝐻 → ( 𝐺 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝐺𝐺 ) ) ) ) = ( 𝐺 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝐺𝐺 ) ) ) ) )
10 id ( 𝑥 = 𝑧𝑥 = 𝑧 )
11 10 10 coeq12d ( 𝑥 = 𝑧 → ( 𝑥𝑥 ) = ( 𝑧𝑧 ) )
12 11 oveq2d ( 𝑥 = 𝑧 → ( 𝑇op ( 𝑥𝑥 ) ) = ( 𝑇op ( 𝑧𝑧 ) ) )
13 12 oveq2d ( 𝑥 = 𝑧 → ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑥𝑥 ) ) ) = ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑧𝑧 ) ) ) )
14 10 13 oveq12d ( 𝑥 = 𝑧 → ( 𝑥 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑥𝑥 ) ) ) ) = ( 𝑧 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑧𝑧 ) ) ) ) )
15 eqidd ( 𝑦 = 𝑤 → ( 𝑧 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑧𝑧 ) ) ) ) = ( 𝑧 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑧𝑧 ) ) ) ) )
16 14 15 cbvmpov ( 𝑥 ∈ HrmOp , 𝑦 ∈ HrmOp ↦ ( 𝑥 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑥𝑥 ) ) ) ) ) = ( 𝑧 ∈ HrmOp , 𝑤 ∈ HrmOp ↦ ( 𝑧 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑧𝑧 ) ) ) ) )
17 2 16 eqtri 𝑆 = ( 𝑧 ∈ HrmOp , 𝑤 ∈ HrmOp ↦ ( 𝑧 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝑧𝑧 ) ) ) ) )
18 ovex ( 𝐺 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝐺𝐺 ) ) ) ) ∈ V
19 8 9 17 18 ovmpo ( ( 𝐺 ∈ HrmOp ∧ 𝐻 ∈ HrmOp ) → ( 𝐺 𝑆 𝐻 ) = ( 𝐺 +op ( ( 1 / 2 ) ·op ( 𝑇op ( 𝐺𝐺 ) ) ) ) )