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divccncf
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Metamath Proof Explorer
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Theorem
divccncf
Description:
Division by a constant is continuous.
(Contributed by
Paul Chapman
, 28-Nov-2007)
Ref
Expression
Hypothesis
divccncf.1
⊢
F
=
x
∈
ℂ
⟼
x
A
Assertion
divccncf
⊢
A
∈
ℂ
∧
A
≠
0
→
F
:
ℂ
⟶
cn
ℂ
Proof
Step
Hyp
Ref
Expression
1
divccncf.1
⊢
F
=
x
∈
ℂ
⟼
x
A
2
divrec2
⊢
x
∈
ℂ
∧
A
∈
ℂ
∧
A
≠
0
→
x
A
=
1
A
⁢
x
3
2
3expb
⊢
x
∈
ℂ
∧
A
∈
ℂ
∧
A
≠
0
→
x
A
=
1
A
⁢
x
4
3
ancoms
⊢
A
∈
ℂ
∧
A
≠
0
∧
x
∈
ℂ
→
x
A
=
1
A
⁢
x
5
4
mpteq2dva
⊢
A
∈
ℂ
∧
A
≠
0
→
x
∈
ℂ
⟼
x
A
=
x
∈
ℂ
⟼
1
A
⁢
x
6
1
5
syl5eq
⊢
A
∈
ℂ
∧
A
≠
0
→
F
=
x
∈
ℂ
⟼
1
A
⁢
x
7
reccl
⊢
A
∈
ℂ
∧
A
≠
0
→
1
A
∈
ℂ
8
eqid
⊢
x
∈
ℂ
⟼
1
A
⁢
x
=
x
∈
ℂ
⟼
1
A
⁢
x
9
8
mulc1cncf
⊢
1
A
∈
ℂ
→
x
∈
ℂ
⟼
1
A
⁢
x
:
ℂ
⟶
cn
ℂ
10
7
9
syl
⊢
A
∈
ℂ
∧
A
≠
0
→
x
∈
ℂ
⟼
1
A
⁢
x
:
ℂ
⟶
cn
ℂ
11
6
10
eqeltrd
⊢
A
∈
ℂ
∧
A
≠
0
→
F
:
ℂ
⟶
cn
ℂ