Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Infinity
Transitive closure of a relation
ttrclexg
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dfttrcl2
Metamath Proof Explorer
Ascii
Unicode
Theorem
ttrclexg
Description:
If
R
is a set, then so is
t++ R
.
(Contributed by
Scott Fenton
, 26-Oct-2024)
Ref
Expression
Assertion
ttrclexg
⊢
R
∈
V
→
t++
R
∈
V
Proof
Step
Hyp
Ref
Expression
1
dmexg
⊢
R
∈
V
→
dom
⁡
R
∈
V
2
rnexg
⊢
R
∈
V
→
ran
⁡
R
∈
V
3
1
2
xpexd
⊢
R
∈
V
→
dom
⁡
R
×
ran
⁡
R
∈
V
4
relttrcl
⊢
Rel
⁡
t++
R
5
relssdmrn
⊢
Rel
⁡
t++
R
→
t++
R
⊆
dom
⁡
t++
R
×
ran
⁡
t++
R
6
4
5
ax-mp
⊢
t++
R
⊆
dom
⁡
t++
R
×
ran
⁡
t++
R
7
dmttrcl
⊢
dom
⁡
t++
R
=
dom
⁡
R
8
rnttrcl
⊢
ran
⁡
t++
R
=
ran
⁡
R
9
7
8
xpeq12i
⊢
dom
⁡
t++
R
×
ran
⁡
t++
R
=
dom
⁡
R
×
ran
⁡
R
10
6
9
sseqtri
⊢
t++
R
⊆
dom
⁡
R
×
ran
⁡
R
11
10
a1i
⊢
R
∈
V
→
t++
R
⊆
dom
⁡
R
×
ran
⁡
R
12
3
11
ssexd
⊢
R
∈
V
→
t++
R
∈
V