Metamath Proof Explorer
Description: Define reflexive relation; relation R is reflexive over the set
A iff A. x e. A x R x . (Contributed by David A. Wheeler, 1-Dec-2019)
|
|
Ref |
Expression |
|
Assertion |
df-reflexive |
⊢ ( 𝑅 Reflexive 𝐴 ↔ ( 𝑅 ⊆ ( 𝐴 × 𝐴 ) ∧ ∀ 𝑥 ∈ 𝐴 𝑥 𝑅 𝑥 ) ) |
Detailed syntax breakdown
| Step |
Hyp |
Ref |
Expression |
| 0 |
|
cR |
⊢ 𝑅 |
| 1 |
|
cA |
⊢ 𝐴 |
| 2 |
1 0
|
wreflexive |
⊢ 𝑅 Reflexive 𝐴 |
| 3 |
1 1
|
cxp |
⊢ ( 𝐴 × 𝐴 ) |
| 4 |
0 3
|
wss |
⊢ 𝑅 ⊆ ( 𝐴 × 𝐴 ) |
| 5 |
|
vx |
⊢ 𝑥 |
| 6 |
5
|
cv |
⊢ 𝑥 |
| 7 |
6 6 0
|
wbr |
⊢ 𝑥 𝑅 𝑥 |
| 8 |
7 5 1
|
wral |
⊢ ∀ 𝑥 ∈ 𝐴 𝑥 𝑅 𝑥 |
| 9 |
4 8
|
wa |
⊢ ( 𝑅 ⊆ ( 𝐴 × 𝐴 ) ∧ ∀ 𝑥 ∈ 𝐴 𝑥 𝑅 𝑥 ) |
| 10 |
2 9
|
wb |
⊢ ( 𝑅 Reflexive 𝐴 ↔ ( 𝑅 ⊆ ( 𝐴 × 𝐴 ) ∧ ∀ 𝑥 ∈ 𝐴 𝑥 𝑅 𝑥 ) ) |