Database
BASIC ALGEBRAIC STRUCTURES
Rings
Definition and basic properties of unital rings
ringn0
Next ⟩
ringlghm
Metamath Proof Explorer
Ascii
Unicode
Theorem
ringn0
Description:
Rings exist.
(Contributed by
AV
, 29-Apr-2019)
Ref
Expression
Assertion
ringn0
⊢
Ring
≠
∅
Proof
Step
Hyp
Ref
Expression
1
vex
⊢
z
∈
V
2
eqid
⊢
Base
ndx
z
+
ndx
z
z
z
⋅
ndx
z
z
z
=
Base
ndx
z
+
ndx
z
z
z
⋅
ndx
z
z
z
3
2
ring1
⊢
z
∈
V
→
Base
ndx
z
+
ndx
z
z
z
⋅
ndx
z
z
z
∈
Ring
4
ne0i
⊢
Base
ndx
z
+
ndx
z
z
z
⋅
ndx
z
z
z
∈
Ring
→
Ring
≠
∅
5
1
3
4
mp2b
⊢
Ring
≠
∅