Database
SUPPLEMENTARY MATERIAL (USERS' MATHBOXES)
Mathbox for Steven Nguyen
Real subtraction
sn-subcl
Next ⟩
sn-subf
Metamath Proof Explorer
Ascii
Unicode
Theorem
sn-subcl
Description:
subcl
without
ax-mulcom
.
(Contributed by
SN
, 5-May-2024)
Ref
Expression
Assertion
sn-subcl
⊢
A
∈
ℂ
∧
B
∈
ℂ
→
A
−
B
∈
ℂ
Proof
Step
Hyp
Ref
Expression
1
subval
⊢
A
∈
ℂ
∧
B
∈
ℂ
→
A
−
B
=
ι
x
∈
ℂ
|
B
+
x
=
A
2
sn-subeu
⊢
B
∈
ℂ
∧
A
∈
ℂ
→
∃!
x
∈
ℂ
B
+
x
=
A
3
2
ancoms
⊢
A
∈
ℂ
∧
B
∈
ℂ
→
∃!
x
∈
ℂ
B
+
x
=
A
4
riotacl
⊢
∃!
x
∈
ℂ
B
+
x
=
A
→
ι
x
∈
ℂ
|
B
+
x
=
A
∈
ℂ
5
3
4
syl
⊢
A
∈
ℂ
∧
B
∈
ℂ
→
ι
x
∈
ℂ
|
B
+
x
=
A
∈
ℂ
6
1
5
eqeltrd
⊢
A
∈
ℂ
∧
B
∈
ℂ
→
A
−
B
∈
ℂ