Database
BASIC ALGEBRAIC STRUCTURES
The complex numbers as an algebraic extensible structure
The ordered field of real numbers
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Metamath Proof Explorer
Ascii
Unicode
Theorem
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Description:
The real numbers form a field.
(Contributed by
Thierry Arnoux
, 1-Nov-2017)
Ref
Expression
Assertion
refld
⊢
ℝ
fld
∈
Field
Proof
Step
Hyp
Ref
Expression
1
resubdrg
⊢
ℝ
∈
SubRing
⁡
ℂ
fld
∧
ℝ
fld
∈
DivRing
2
1
simpri
⊢
ℝ
fld
∈
DivRing
3
df-refld
⊢
ℝ
fld
=
ℂ
fld
↾
𝑠
ℝ
4
cncrng
⊢
ℂ
fld
∈
CRing
5
1
simpli
⊢
ℝ
∈
SubRing
⁡
ℂ
fld
6
eqid
⊢
ℂ
fld
↾
𝑠
ℝ
=
ℂ
fld
↾
𝑠
ℝ
7
6
subrgcrng
⊢
ℂ
fld
∈
CRing
∧
ℝ
∈
SubRing
⁡
ℂ
fld
→
ℂ
fld
↾
𝑠
ℝ
∈
CRing
8
4
5
7
mp2an
⊢
ℂ
fld
↾
𝑠
ℝ
∈
CRing
9
3
8
eqeltri
⊢
ℝ
fld
∈
CRing
10
isfld
⊢
ℝ
fld
∈
Field
↔
ℝ
fld
∈
DivRing
∧
ℝ
fld
∈
CRing
11
2
9
10
mpbir2an
⊢
ℝ
fld
∈
Field