Metamath Proof Explorer


Theorem pjmulii

Description: Projection of (scalar) product is product of projection. (Contributed by NM, 31-Oct-1999) (New usage is discouraged.)

Ref Expression
Hypotheses pjidm.1 𝐻C
pjidm.2 𝐴 ∈ ℋ
pjmul.3 𝐶 ∈ ℂ
Assertion pjmulii ( ( proj𝐻 ) ‘ ( 𝐶 · 𝐴 ) ) = ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) )

Proof

Step Hyp Ref Expression
1 pjidm.1 𝐻C
2 pjidm.2 𝐴 ∈ ℋ
3 pjmul.3 𝐶 ∈ ℂ
4 1 2 pjpji 𝐴 = ( ( ( proj𝐻 ) ‘ 𝐴 ) + ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) )
5 4 oveq2i ( 𝐶 · 𝐴 ) = ( 𝐶 · ( ( ( proj𝐻 ) ‘ 𝐴 ) + ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) )
6 1 2 pjhclii ( ( proj𝐻 ) ‘ 𝐴 ) ∈ ℋ
7 1 choccli ( ⊥ ‘ 𝐻 ) ∈ C
8 7 2 pjhclii ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ∈ ℋ
9 3 6 8 hvdistr1i ( 𝐶 · ( ( ( proj𝐻 ) ‘ 𝐴 ) + ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) ) = ( ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) ) + ( 𝐶 · ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) )
10 5 9 eqtri ( 𝐶 · 𝐴 ) = ( ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) ) + ( 𝐶 · ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) )
11 10 fveq2i ( ( proj𝐻 ) ‘ ( 𝐶 · 𝐴 ) ) = ( ( proj𝐻 ) ‘ ( ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) ) + ( 𝐶 · ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) ) )
12 1 chshii 𝐻S
13 1 2 pjclii ( ( proj𝐻 ) ‘ 𝐴 ) ∈ 𝐻
14 shmulcl ( ( 𝐻S𝐶 ∈ ℂ ∧ ( ( proj𝐻 ) ‘ 𝐴 ) ∈ 𝐻 ) → ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) ) ∈ 𝐻 )
15 12 3 13 14 mp3an ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) ) ∈ 𝐻
16 7 chshii ( ⊥ ‘ 𝐻 ) ∈ S
17 7 2 pjclii ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ∈ ( ⊥ ‘ 𝐻 )
18 shmulcl ( ( ( ⊥ ‘ 𝐻 ) ∈ S𝐶 ∈ ℂ ∧ ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ∈ ( ⊥ ‘ 𝐻 ) ) → ( 𝐶 · ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) ∈ ( ⊥ ‘ 𝐻 ) )
19 16 3 17 18 mp3an ( 𝐶 · ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) ∈ ( ⊥ ‘ 𝐻 )
20 1 pjcompi ( ( ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) ) ∈ 𝐻 ∧ ( 𝐶 · ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) ∈ ( ⊥ ‘ 𝐻 ) ) → ( ( proj𝐻 ) ‘ ( ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) ) + ( 𝐶 · ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) ) ) = ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) ) )
21 15 19 20 mp2an ( ( proj𝐻 ) ‘ ( ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) ) + ( 𝐶 · ( ( proj ‘ ( ⊥ ‘ 𝐻 ) ) ‘ 𝐴 ) ) ) ) = ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) )
22 11 21 eqtri ( ( proj𝐻 ) ‘ ( 𝐶 · 𝐴 ) ) = ( 𝐶 · ( ( proj𝐻 ) ‘ 𝐴 ) )