Database
REAL AND COMPLEX NUMBERS
Real and complex numbers - basic operations
Division
div23
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div32
Metamath Proof Explorer
Ascii
Unicode
Theorem
div23
Description:
A commutative/associative law for division.
(Contributed by
NM
, 2-Aug-2004)
Ref
Expression
Assertion
div23
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
A
⁢
B
C
=
A
C
⁢
B
Proof
Step
Hyp
Ref
Expression
1
mulcom
⊢
A
∈
ℂ
∧
B
∈
ℂ
→
A
⁢
B
=
B
⁢
A
2
1
oveq1d
⊢
A
∈
ℂ
∧
B
∈
ℂ
→
A
⁢
B
C
=
B
⁢
A
C
3
2
3adant3
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
A
⁢
B
C
=
B
⁢
A
C
4
divass
⊢
B
∈
ℂ
∧
A
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
B
⁢
A
C
=
B
⁢
A
C
5
4
3com12
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
B
⁢
A
C
=
B
⁢
A
C
6
simp2
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
B
∈
ℂ
7
divcl
⊢
A
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
A
C
∈
ℂ
8
7
3expb
⊢
A
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
A
C
∈
ℂ
9
8
3adant2
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
A
C
∈
ℂ
10
6
9
mulcomd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
B
⁢
A
C
=
A
C
⁢
B
11
3
5
10
3eqtrd
⊢
A
∈
ℂ
∧
B
∈
ℂ
∧
C
∈
ℂ
∧
C
≠
0
→
A
⁢
B
C
=
A
C
⁢
B