Database
REAL AND COMPLEX NUMBERS
Construction and axiomatization of real and complex numbers
Real and complex number postulates restated as axioms
ax-mulass
Metamath Proof Explorer
Description: Multiplication of complex numbers is associative. Axiom 10 of 22 for real
and complex numbers, justified by Theorem axmulass . Proofs should
normally use mulass instead. (New usage is discouraged.) (Contributed by NM , 22-Nov-1994)
Ref
Expression
Assertion
ax-mulass
⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐶 ∈ ℂ ) → ( ( 𝐴 · 𝐵 ) · 𝐶 ) = ( 𝐴 · ( 𝐵 · 𝐶 ) ) )
Detailed syntax breakdown
Step
Hyp
Ref
Expression
0
cA
⊢ 𝐴
1
cc
⊢ ℂ
2
0 1
wcel
⊢ 𝐴 ∈ ℂ
3
cB
⊢ 𝐵
4
3 1
wcel
⊢ 𝐵 ∈ ℂ
5
cC
⊢ 𝐶
6
5 1
wcel
⊢ 𝐶 ∈ ℂ
7
2 4 6
w3a
⊢ ( 𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐶 ∈ ℂ )
8
cmul
⊢ ·
9
0 3 8
co
⊢ ( 𝐴 · 𝐵 )
10
9 5 8
co
⊢ ( ( 𝐴 · 𝐵 ) · 𝐶 )
11
3 5 8
co
⊢ ( 𝐵 · 𝐶 )
12
0 11 8
co
⊢ ( 𝐴 · ( 𝐵 · 𝐶 ) )
13
10 12
wceq
⊢ ( ( 𝐴 · 𝐵 ) · 𝐶 ) = ( 𝐴 · ( 𝐵 · 𝐶 ) )
14
7 13
wi
⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐵 ∈ ℂ ∧ 𝐶 ∈ ℂ ) → ( ( 𝐴 · 𝐵 ) · 𝐶 ) = ( 𝐴 · ( 𝐵 · 𝐶 ) ) )