Statement List for Metamath Proof Explorer - 3201-3300 - Page 33 of 58
| Type | Label | Description |
| Statement |
| |
| Theorem | er2 3201 |
Alternate definition of equivalence predicate.
|
| ⊢
(Er R ↔ ∀x∀y∀z((xRy →
yRx) ∧
((xRy ∧
yRz) →
xRz))) |
| |
| Definition | df-ec 3202 |
Define the R -coset of A. Exercise 35 of [Enderton] p. 61. This
is called the equivalence class of A
modulo R when R is an
equivalence relation. The Definition of [Enderton] p. 57 uses the
notation [A] (subscript) R, although we simply follow the
brackets by R since we don't have
subscripts.
For an alternate definition, see ec2 3203.
|
| ⊢
[A]R = (R “
{A}) |
| |
| Theorem | ec2 3203 |
Alternate definition of R-coset of A. Definition 34 of
[Suppes] p. 81.
|
| ⊢
A ∈ V
⇒ ⊢ [A]R = {y∣ARy} |
| |
| Theorem | ecexg 3204 |
An equivalence class modulo a set is a set.
|
| ⊢
(R ∈ B → [A]R ∈
V) |
| |
| Definition | df-qs 3205 |
Define quotient set. R is usually an
equivalence relation.
Definition of [Enderton] p. 58.
|
| ⊢
(A / R) = {y∣∃x ∈ A
y = [x]R} |
| |
| Theorem | ereq 3206 |
Equality theorem for equivalence predicate.
|
| ⊢
(R = S → (Er R
↔ Er S)) |
| |
| Theorem | ster 3207 |
A symmetric, transitive relation is an equivalence relation.
|
| ⊢
(xRy →
yRx) & ⊢ ((xRy ∧
yRz) →
xRz) ⇒ ⊢ Er R |
| |
| Theorem | ider 3208 |
The identity relation is an equivalence relation.
|
| ⊢
Er I |
| |
| Theorem | ersym 3209 |
An equivalence relation is symmetric.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
& ⊢ Er R ⇒ ⊢ (ARB →
BRA) |
| |
| Theorem | ersymb 3210 |
An equivalence relation is symmetric.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
& ⊢ Er R ⇒ ⊢ (ARB ↔
BRA) |
| |
| Theorem | ertr 3211 |
An equivalence relation is transitive.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
& ⊢ C ∈ V
& ⊢ Er R ⇒ ⊢ ((ARB ∧
BRC) →
ARC) |
| |
| Theorem | erref 3212 |
An equivalence relation is reflexive on its field. Compare
Theorem 3M of [Enderton] p. 56.
|
| ⊢
Er R
⇒ ⊢ (A ∈ (dom R
∪ ran R) → ARA) |
| |
| Theorem | erdmrn 3213 |
The range and domain of an equivalence relation are equal.
|
| ⊢
Er R
⇒ ⊢ dom R = ran R |
| |
| Theorem | eceq1 3214 |
Equality theorem for equivalence class.
|
| ⊢
(A = B → [C]A = [C]B) |
| |
| Theorem | eceq2 3215 |
Equality theorem for equivalence class.
|
| ⊢
(A = B → [A]C = [B]C) |
| |
| Theorem | elec 3216 |
Membership in an equivalence class. Theorem 72 of [Suppes] p. 82.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
⇒ ⊢ (A ∈ [B]R ↔
BRA) |
| |
| Theorem | ecdmn0 3217 |
An equivalence class is not empty in its domain.
|
| ⊢
A ∈ V
⇒ ⊢ (A ∈ dom R
↔ ¬ [A]R = ∅) |
| |
| Theorem | erthi 3218 |
Basic property of equivalence relations. Part of Lemma 3N of [Enderton]
p. 57.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
& ⊢ Er R ⇒ ⊢ (ARB →
[A]R =
[B]R) |
| |
| Theorem | erth 3219 |
Basic property of equivalence relations. Theorem 73 of [Suppes]
p. 82.
|
| ⊢
B ∈ V
& ⊢ Er R ⇒ ⊢ (A ∈
(dom R ∪ ran R) → ([A]R = [B]R ↔
ARB)) |
| |
| Theorem | erthdm 3220 |
Basic property of equivalence relations. Compare Theorem 73 of [Suppes]
p. 82. Assumes membership in the domain instead of just the field.
|
| ⊢
B ∈ V
& ⊢ Er R ⇒ ⊢ (A ∈
dom R → ([A]R = [B]R ↔
ARB)) |
| |
| Theorem | erthdmr 3221 |
Basic property of equivalence relations. Compare Theorem 73 of [Suppes]
p. 82. Assumes membership of the second argument in the domain.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
& ⊢ Er R ⇒ ⊢ (B ∈
dom R → ([A]R = [B]R ↔
ARB)) |
| |
| Theorem | ereldm 3222 |
Equality of equivalence classes implies equivalence of domain
membership.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
& ⊢ Er R & ⊢ dom R =
D
⇒ ⊢ ([A]R = [B]R →
(A ∈ D ↔ B
∈ D)) |
| |
| Theorem | erdisj 3223 |
Equivalence classes do not overlap. In other words, two equivalence
classes are either equal or disjoint. Theorem 74 of [Suppes] p. 83.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
& ⊢ Er R ⇒ ⊢ ([A]R = [B]R ∨
([A]R
∩ [B]R) = ∅) |
| |
| Theorem | ecidsn 3224 |
An equivalence class modulo the identity relation is a singleton.
|
| ⊢
[A]I = {A} |
| |
| Theorem | qseq1 3225 |
Equality theorem for quotient set.
|
| ⊢
(A = B → (A
/ C) = (B / C)) |
| |
| Theorem | qseq2 3226 |
Equality theorem for quotient set.
|
| ⊢
(A = B → (C
/ A) = (C / B)) |
| |
| Theorem | elqs 3227 |
Membership in a quotient set.
|
| ⊢
B ∈ V
⇒ ⊢ (B ∈ (A
/ R) ↔ ∃x(x ∈
A ∧ B = [x]R)) |
| |
| Theorem | elqsi 3228 |
Membership in a quotient set.
|
| ⊢
(B ∈ (A / R)
→ ∃x(x ∈ A
∧ B = [x]R)) |
| |
| Theorem | ecelqsi 3229 |
Membership of an equivalence class in a quotient set.
|
| ⊢
R ∈ V
⇒ ⊢ (B ∈ A
→ [B]R ∈ (A
/ R)) |
| |
| Theorem | ecopqsi 3230 |
"Closure" law for equivalence class of ordered pairs.
|
| ⊢
R ∈ V
& ⊢ S = ((A ×
A) / R) ⇒ ⊢ ((B ∈
A ∧ C ∈ A)
→ [〈B, C〉]R
∈ S) |
| |
| Theorem | qsex 3231 |
A quotient set exists.
|
| ⊢
A ∈ V
⇒ ⊢ (A / R)
∈ V |
| |
| Theorem | snec 3232 |
The singleton of an equivalence class.
|
| ⊢
A ∈ V
⇒ ⊢ {[A]R} =
({A} / R) |
| |
| Theorem | ecqs 3233 |
Equivalence class in terms of quotient set.
|
| ⊢
A ∈ V
& ⊢ R ∈ V
⇒ ⊢ [A]R = ∪({A} /
R) |
| |
| Theorem | 0nelqs 3234 |
A quotient set doesn't contain the empty set.
|
| ⊢
Er R
& ⊢ dom R = A ⇒ ⊢ ¬ ∅ ∈ (A / R) |
| |
| Theorem | ecelqsdm 3235 |
Membership of an equivalence class in a quotient set.
|
| ⊢
B ∈ V
& ⊢ Er R & ⊢ dom R =
A
⇒ ⊢ ([B]R ∈
(A / R) → B
∈ A) |
| |
| Theorem | ecid 3236 |
A set is equal to its converse epsilon coset. (Note: converse epsilon
is not an equivalence relation.)
|
| ⊢
A ∈ V
⇒ ⊢ [A]◡E
= A |
| |
| Theorem | qsid 3237 |
A set is equal to its quotient set mod converse epsilon. (Note: converse
epsilon is not an equivalence relation.)
|
| ⊢
A ∈ V
⇒ ⊢ (A / ◡E) = A |
| |
| Theorem | ectocl 3238 |
Implicit substitution of class for equivalence class.
|
| ⊢
S = (B / R) & ⊢ ([x]R = A → (φ
↔ ψ))
& ⊢ (x ∈ B
→ φ)
⇒ ⊢ (A ∈ S
→ ψ) |
| |
| Theorem | ecoptocl 3239 |
Implicit substitution of class for equivalence class of ordered pair.
|
| ⊢
S = ((B × C)
/ R)
& ⊢ ([〈x, y〉]R =
A → (φ ↔ ψ))
& ⊢ ((x ∈ B
∧ y ∈ C) → φ)
⇒ ⊢ (A ∈ S
→ ψ) |
| |
| Theorem | 2ecoptocl 3240 |
Implicit substitution of classes for equivalence classes of ordered
pairs.
|
| ⊢
S = ((C × D)
/ R)
& ⊢ ([〈x, y〉]R =
A → (φ ↔ ψ))
& ⊢ ([〈z, w〉]R =
B → (ψ ↔ χ))
& ⊢ (((x ∈ C
∧ y ∈ D) ∧ (z
∈ C ∧ w ∈ D))
→ φ)
⇒ ⊢ ((A ∈ S
∧ B ∈ S) → χ) |
| |
| Theorem | 3ecoptocl 3241 |
Implicit substitution of classes for equivalence classes of ordered
pairs.
|
| ⊢
S = ((D × D)
/ R)
& ⊢ ([〈x, y〉]R =
A → (φ ↔ ψ))
& ⊢ ([〈z, w〉]R =
B → (ψ ↔ χ))
& ⊢ ([〈v, u〉]R =
C → (χ ↔ θ))
& ⊢ (((x ∈ D
∧ y ∈ D) ∧ (z
∈ D ∧ w ∈ D)
∧ (v ∈ D ∧ u
∈ D)) → φ)
⇒ ⊢ ((A ∈ S
∧ B ∈ S ∧ C
∈ S) → θ) |
| |
| Theorem | brecop 3242 |
Binary relation on a quotient set. Lemma for real number
construction.
|
| ⊢
S ∈ V
& ⊢ Er S & ⊢ dom S =
(G × G) & ⊢ H =
((G × G) / S) & ⊢ R =
{〈x, y〉∣((x ∈ H
∧ y ∈ H) ∧ ∃z∃w∃v∃u((x =
[〈z, w〉]S ∧
y = [〈v, u〉]S)
∧ φ))}
& ⊢ ((((z ∈ G
∧ w ∈ G) ∧ (A
∈ G ∧ B ∈ G))
∧ ((v ∈ G ∧ u
∈ G) ∧ (C ∈ G
∧ D ∈ G))) → (([〈z, w〉]S =
[〈A, B〉]S ∧
[〈v, u〉]S =
[〈C, D〉]S)
→ (φ ↔ ψ)))
⇒ ⊢ (((A ∈ G
∧ B ∈ G) ∧ (C
∈ G ∧ D ∈ G))
→ ([〈A, B〉]SR[〈C,
D〉]S ↔ ψ)) |
| |
| Theorem | brecop2 3243 |
Binary relation on a quotient set. Lemma for real number
construction. Eliminates antecedent from last hypothesis.
|
| ⊢
S ∈ V
& ⊢ B ∈ V
& ⊢ C ∈ V
& ⊢ D ∈ V
& ⊢ Er S & ⊢ dom S =
(G × G) & ⊢ H =
((G × G) / S) & ⊢ R ⊆
(H × H) & ⊢ Q ⊆
(G × G) & ⊢ ¬ ∅ ∈ G & ⊢ dom F =
(G × G) & ⊢ (((A ∈
G ∧ B ∈ G)
∧ (C ∈ G ∧ D
∈ G)) → ([〈A, B〉]SR[〈C,
D〉]S ↔ (AFD)Q(BFC)))
⇒ ⊢ ([〈A, B〉]SR[〈C,
D〉]S ↔ (AFD)Q(BFC)) |
| |
| Theorem | ecopopreq 3244 |
Express the relation R (specified by the
hypothesis) in terms of
its operation F.
|
| ⊢
R = {〈x, y〉∣((x ∈ (S
× S) ∧ y ∈ (S
× S)) ∧ ∃z∃w∃v∃u((x =
〈z, w〉 ∧ y
= 〈v, u〉) ∧ (zFu) = (wFv)))}
⇒ ⊢ (((A ∈ S
∧ B ∈ S) ∧ (C
∈ S ∧ D ∈ S))
→ (〈A, B〉R〈C,
D〉 ↔ (AFD) = (BFC))) |
| |
| Theorem | ecopoprdm 3245 |
Assuming the operation F is commutative,
compute the domain the
relation R specified by the first
hypothesis.
|
| ⊢
R = {〈x, y〉∣((x ∈ (S
× S) ∧ y ∈ (S
× S)) ∧ ∃z∃w∃v∃u((x =
〈z, w〉 ∧ y
= 〈v, u〉) ∧ (zFu) = (wFv)))}
& ⊢ (xFy) = (yFx) ⇒ ⊢ dom R =
(S × S) |
| |
| Theorem | ecopoprsym 3246 |
Assuming the operation F is commutative,
show that the relation
R, specified by the first
hypothesis, is symmetric.
|
| ⊢
R = {〈x, y〉∣((x ∈ (S
× S) ∧ y ∈ (S
× S)) ∧ ∃z∃w∃v∃u((x =
〈z, w〉 ∧ y
= 〈v, u〉) ∧ (zFu) = (wFv)))}
& ⊢ (xFy) = (yFx) & ⊢ B ∈
V ⇒ ⊢ (ARB →
BRA) |
| |
| Theorem | ecopoprtrn 3247 |
Assuming that operation F is commutative
(second hypothesis),
closed (third hypothesis), associative (fourth hypothesis), and
has the cancellation property (fifth hypothesis), show that the
relation R, specified by the
first hypothesis, is
transitive.
|
| ⊢
R = {〈x, y〉∣((x ∈ (S
× S) ∧ y ∈ (S
× S)) ∧ ∃z∃w∃v∃u((x =
〈z, w〉 ∧ y
= 〈v, u〉) ∧ (zFu) = (wFv)))}
& ⊢ (xFy) = (yFx) & ⊢ ((x ∈
S ∧ y ∈ S)
→ (xFy) ∈
S)
& ⊢ ((xFy)Fz) = (xF(yFz)) & ⊢ ((x ∈
S ∧ y ∈ S)
→ ((xFy) = (xFz) → y =
z))
& ⊢ B ∈ V
& ⊢ C ∈ V
⇒ ⊢ ((ARB ∧ BRC) → ARC) |
| |
| Theorem | ecopoprer 3248 |
Assuming that operation F is commutative
(second hypothesis),
closed (third hypothesis), associative (fourth hypothesis), and
has the cancellation property (fifth hypothesis), show that the
relation R, specified by the
first hypothesis, is an
equivalence relation.
|
| ⊢
R = {〈x, y〉∣((x ∈ (S
× S) ∧ y ∈ (S
× S)) ∧ ∃z∃w∃v∃u((x =
〈z, w〉 ∧ y
= 〈v, u〉) ∧ (zFu) = (wFv)))}
& ⊢ (xFy) = (yFx) & ⊢ ((x ∈
S ∧ y ∈ S)
→ (xFy) ∈
S)
& ⊢ ((xFy)Fz) = (xF(yFz)) & ⊢ ((x ∈
S ∧ y ∈ S)
→ ((xFy) = (xFz) → y =
z))
⇒ ⊢ Er R |
| |
| Theorem | eceqopreq 3249 |
Equality of equivalence relation in terms of an operation.
|
| ⊢
B ∈ V
& ⊢ C ∈ V
& ⊢ D ∈ V
& ⊢ Er R & ⊢ dom R =
(S × S) & ⊢ dom F =
(S × S) & ⊢ ¬ ∅ ∈ S & ⊢ ((x ∈
S ∧ y ∈ S)
→ (xFy) ∈
S)
& ⊢ (((A ∈ S
∧ B ∈ S) ∧ (C
∈ S ∧ D ∈ S))
→ (〈A, B〉R〈C,
D〉 ↔ (AFD) = (BFC)))
⇒ ⊢ ((A ∈ S
∧ C ∈ S) → ([〈A, B〉]R =
[〈C, D〉]R
↔ (AFD) = (BFC))) |
| |
| Theorem | th3qlem1 3250 |
Lemma for Exercise 44 version of Theorem 3Q of [Enderton] p. 60. The
third hypothesis is the compatibility assumption.
|
| ⊢
Er R
& ⊢ dom R = S & ⊢ (((y ∈
S ∧ w ∈ S)
∧ (z ∈ S ∧ v
∈ S)) → ((yRw ∧ zRv) → (yFz)R(wFv)))
⇒ ⊢ ((A ∈ (S
/ R) ∧ B ∈ (S
/ R)) → ∃*x∃y∃z((A =
[y]R
∧ B = [z]R) ∧
x = [(yFz)]R)) |
| |
| Theorem | th3qlem2 3251 |
Lemma for Exercise 44 version of Theorem 3Q of [Enderton] p. 60,
extended to operations on ordered pairs. The fourth hypothesis is the
compatibility assumption.
|
| ⊢
R ∈ V
& ⊢ Er R & ⊢ dom R =
(S × S) & ⊢ ((((w
∈ S ∧ v ∈ S)
∧ (u ∈ S ∧ t
∈ S)) ∧ ((s ∈ S
∧ f ∈ S) ∧ (g
∈ S ∧ h ∈ S)))
→ ((〈w, v〉R〈u,
t〉 ∧ 〈s, f〉R〈g,
h〉) → (〈w, v〉F〈s,
f〉)R(〈u,
t〉F〈g,
h〉)))
⇒ ⊢ ((A ∈ ((S
× S) / R) ∧ B
∈ ((S × S) / R))
→ ∃*z∃w∃v∃u∃t((A =
[〈w, v〉]R ∧
B = [〈u, t〉]R)
∧ z = [(〈w, v〉F〈u,
t〉)]R)) |
| |
| Theorem | th3qcor 3252 |
Corollary of Theorem 3Q of [Enderton] p. 60.
|
| ⊢
R ∈ V
& ⊢ Er R & ⊢ dom R =
(S × S) & ⊢ ((((w
∈ S ∧ v ∈ S)
∧ (u ∈ S ∧ t
∈ S)) ∧ ((s ∈ S
∧ f ∈ S) ∧ (g
∈ S ∧ h ∈ S)))
→ ((〈w, v〉R〈u,
t〉 ∧ 〈s, f〉R〈g,
h〉) → (〈w, v〉F〈s,
f〉)R(〈u,
t〉F〈g,
h〉)))
& ⊢ G = {〈〈x, y〉,
z〉∣((x ∈ ((S
× S) / R) ∧ y
∈ ((S × S) / R))
∧ ∃w∃v∃u∃t((x =
[〈w, v〉]R ∧
y = [〈u, t〉]R)
∧ z = [(〈w, v〉F〈u,
t〉)]R))}
⇒ ⊢ Fun G |
| |
| Theorem | th3q 3253 |
Theorem 3Q of [Enderton] p. 60, extended to
operations on ordered
pairs.
|
| ⊢
R ∈ V
& ⊢ Er R & ⊢ dom R =
(S × S) & ⊢ ((((w
∈ S ∧ v ∈ S)
∧ (u ∈ S ∧ t
∈ S)) ∧ ((s ∈ S
∧ f ∈ S) ∧ (g
∈ S ∧ h ∈ S)))
→ ((〈w, v〉R〈u,
t〉 ∧ 〈s, f〉R〈g,
h〉) → (〈w, v〉F〈s,
f〉)R(〈u,
t〉F〈g,
h〉)))
& ⊢ G = {〈〈x, y〉,
z〉∣((x ∈ ((S
× S) / R) ∧ y
∈ ((S × S) / R))
∧ ∃w∃v∃u∃t((x =
[〈w, v〉]R ∧
y = [〈u, t〉]R)
∧ z = [(〈w, v〉F〈u,
t〉)]R))}
⇒ ⊢ (((A ∈ S
∧ B ∈ S) ∧ (C
∈ S ∧ D ∈ S))
→ ([〈A, B〉]RG[〈C,
D〉]R) = [(〈A,
B〉F〈C,
D〉)]R) |
| |
| Theorem | oprec 3254 |
Express an operation on equivalence classes of ordered pairs in terms
of equivalence class of operations on ordered pairs.
|
| ⊢
H ∈ V
& ⊢ K ∈ V
& ⊢ L ∈ V
& ⊢ R ∈ V
& ⊢ Er R & ⊢ dom R =
(S × S) & ⊢ R =
{〈x, y〉∣((x ∈ (S
× S) ∧ y ∈ (S
× S)) ∧ ∃z∃w∃v∃u((x =
〈z, w〉 ∧ y
= 〈v, u〉) ∧ φ))}
& ⊢ (((z = a ∧
w = b)
∧ (v = c ∧ u =
d)) → (φ ↔ ψ))
& ⊢ (((z = g ∧
w = h)
∧ (v = t ∧ u =
s)) → (φ ↔ χ))
& ⊢ G = {〈〈x, y〉,
z〉∣((x ∈ (S
× S) ∧ y ∈ (S
× S)) ∧ ∃w∃v∃u∃f((x =
〈w, v〉 ∧ y
= 〈u, f〉) ∧ z = J))} & ⊢ (((w =
a ∧ v = b) ∧
(u = g
∧ f = h)) → J =
K)
& ⊢ (((w = c ∧
v = d)
∧ (u = t ∧ f =
s)) → J = L) & ⊢ (((w =
A ∧ v = B) ∧
(u = C
∧ f = D)) → J =
H)
& ⊢ F = {〈〈x, y〉,
z〉∣((x ∈ Q
∧ y ∈ Q) ∧ ∃a∃b∃c∃d((x =
[〈a, b〉]R ∧
y = [〈c, d〉]R)
∧ z = [(〈a, b〉G〈c,
d〉)]R))} & ⊢ Q =
((S × S) / R) & ⊢ ((((a
∈ S ∧ b ∈ S)
∧ (c ∈ S ∧ d
∈ S)) ∧ ((g ∈ S
∧ h ∈ S) ∧ (t
∈ S ∧ s ∈ S)))
→ ((ψ ∧ χ) → KRL))
⇒ ⊢ (((A ∈ S
∧ B ∈ S) ∧ (C
∈ S ∧ D ∈ S))
→ ([〈A, B〉]RF[〈C,
D〉]R) = [H]R) |
| |
| Theorem | ecoprcom 3255 |
Lemma used in proving commutative laws via equivalence classes.
|
| ⊢
C = ((S × S)
/ R)
& ⊢ (((x ∈ S
∧ y ∈ S) ∧ (z
∈ S ∧ w ∈ S))
→ ([〈x, y〉]RF[〈z,
w〉]R) = [〈D,
G〉]R) & ⊢ (((z ∈
S ∧ w ∈ S)
∧ (x ∈ S ∧ y
∈ S)) → ([〈z, w〉]RF[〈x,
y〉]R) = [〈H,
J〉]R) & ⊢ D =
H
& ⊢ G = J ⇒ ⊢ ((A ∈
C ∧ B ∈ C)
→ (AFB) = (BFA)) |
| |
| Theorem | ecoprass 3256 |
Lemma used in proving associative laws via equivalence classes.
|
| ⊢
D = ((S × S)
/ R)
& ⊢ (((x ∈ S
∧ y ∈ S) ∧ (z
∈ S ∧ w ∈ S))
→ ([〈x, y〉]RF[〈z,
w〉]R) = [〈G,
H〉]R) & ⊢ (((z ∈
S ∧ w ∈ S)
∧ (v ∈ S ∧ u
∈ S)) → ([〈z, w〉]RF[〈v,
u〉]R) = [〈N,
Q〉]R) & ⊢ (((G ∈
S ∧ H ∈ S)
∧ (v ∈ S ∧ u
∈ S)) → ([〈G, H〉]RF[〈v,
u〉]R) = [〈J,
K〉]R) & ⊢ (((x ∈
S ∧ y ∈ S)
∧ (N ∈ S ∧ Q
∈ S)) → ([〈x, y〉]RF[〈N,
Q〉]R) = [〈L,
M〉]R) & ⊢ (((x ∈
S ∧ y ∈ S)
∧ (z ∈ S ∧ w
∈ S)) → (G ∈ S
∧ H ∈ S)) & ⊢ (((z ∈
S ∧ w ∈ S)
∧ (v ∈ S ∧ u
∈ S)) → (N ∈ S
∧ Q ∈ S)) & ⊢ J =
L
& ⊢ K = M ⇒ ⊢ ((A ∈
D ∧ B ∈ D
∧ C ∈ D) → ((AFB)FC) = (AF(BFC))) |
| |
| Theorem | ecoprdi 3257 |
Lemma used in proving distributive laws via equivalence classes.
|
| ⊢
D = ((S × S)
/ R)
& ⊢ (((z ∈ S
∧ w ∈ S) ∧ (v
∈ S ∧ u ∈ S))
→ ([〈z, w〉]RF[〈v,
u〉]R) = [〈M,
N〉]R) & ⊢ (((x ∈
S ∧ y ∈ S)
∧ (M ∈ S ∧ N
∈ S)) → ([〈x, y〉]RG[〈M,
N〉]R) = [〈H,
J〉]R) & ⊢ (((x ∈
S ∧ y ∈ S)
∧ (z ∈ S ∧ w
∈ S)) → ([〈x, y〉]RG[〈z,
w〉]R) = [〈W,
X〉]R) & ⊢ (((x ∈
S ∧ y ∈ S)
∧ (v ∈ S ∧ u
∈ S)) → ([〈x, y〉]RG[〈v,
u〉]R) = [〈Y,
Z〉]R) & ⊢ (((W ∈
S ∧ X ∈ S)
∧ (Y ∈ S ∧ Z
∈ S)) → ([〈W, X〉]RF[〈Y,
Z〉]R) = [〈K,
L〉]R) & ⊢ (((z ∈
S ∧ w ∈ S)
∧ (v ∈ S ∧ u
∈ S)) → (M ∈ S
∧ N ∈ S)) & ⊢ (((x ∈
S ∧ y ∈ S)
∧ (z ∈ S ∧ w
∈ S)) → (W ∈ S
∧ X ∈ S)) & ⊢ (((x ∈
S ∧ y ∈ S)
∧ (v ∈ S ∧ u
∈ S)) → (Y ∈ S
∧ Z ∈ S)) & ⊢ H =
K
& ⊢ J = L ⇒ ⊢ ((A ∈
D ∧ B ∈ D
∧ C ∈ D) → (AG(BFC)) = ((AGB)F(AGC))) |
| |
| Syntax | cm 3258 |
Extend the definition of a class to include the mapping operation.
(Read for A ↑m
B, "the set of all functions that map
from
B to A.)
|
| class
↑m |
| |
| Definition | df-map 3259 |
Define the mapping operation or set exponentiation. The set of all
functions that map from B to
A is written (A ↑m B) (see
mapval 3264). Many authors write A followed by B
as a superscript
for this operation and rely on context to avoid confusion other
exponentiation operations (e.g. Definition 10.42 of [TakeutiZaring]
p. 95). Other authors show B as a
prefixed superscript, which is
read "A pre B" (e.g. definition of [Enderton] p. 52).
Definition 8.21 of [Eisenberg] p. 125
uses the notation Map(B,
A) for our (A ↑m B). The up-arrow is used by Donald Knuth
for iterated exponentiation (Science 194, 1235-1242, 1976). We
adopt
the first case of his notation (simple exponentiation) and subscript it
with m to distinguish it from other kinds of exponentiation.
|
| ⊢
↑m = {〈〈x, y〉,
z〉∣z = {f∣f:y–→x}} |
| |
| Theorem | mapprc 3260 |
When A is a proper class, the class of all
functions mapping A
to B is empty. Exercise 4.41 of [Mendelson] p. 255.
|
| ⊢
(¬ A ∈ V →
{f∣f:A–→B} = ∅) |
| |
| Theorem | mapex 3261 |
The class of all functions mapping one set to another is a set. Remark
after Definition 10.24 of [Kunen] p. 31.
(Contributed by Raph Levien,
4-Dec-03.)
|
| ⊢
((A ∈ C ∧ B
∈ D) → {f∣f:A–→B} ∈ V) |
| |
| Theorem | fnmap 3262 |
Set exponentiation has a universal domain.
|
| ⊢
↑m Fn (V × V) |
| |
| Theorem | mapvalg 3263 |
The value of set exponentiation. (A
↑m B) is the set of
all
functions that map from B to
A. Definition 10.24 of [Kunen]
p. 24.
|
| ⊢
((A ∈ C ∧ B
∈ D) → (A ↑m B) = {f∣f:B–→A}) |
| |
| Theorem | mapval 3264 |
The value of set exponentiation (inference version). (A ↑m B)
is the set of all functions that map from B to A.
Definition
10.24 of [Kunen] p. 24.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
⇒ ⊢ (A ↑m B) = {f∣f:B–→A} |
| |
| Theorem | elmap 3265 |
Membership relation for set exponentiation.
|
| ⊢
A ∈ V
& ⊢ B ∈ V
⇒ ⊢ (C ∈ (A
↑m B) ↔
C:B–→A) |
| |
| Theorem | map0e 3266 |
Set exponentiation with an empty exponent (ordinal number 0) is ordinal
number 1. Exercise 4.42(a) of [Mendelson] p. 255.
|
| ⊢
A ∈ V
⇒ ⊢ (A ↑m ∅) =
1o |
| |
| Theorem | map0b 3267 |
Set exponentiation with an empty base is the empty set, provided the
exponent is non-empty. Theorem 96 of [Suppes] p. 89.
|
| ⊢
A ∈ V
⇒ ⊢ (¬ A = ∅ → (∅
↑m A) =
∅) |
| |
| Theorem | map0 3268 |
Set exponentiation is empty iff the base is empty and the exponent is
not empty. Theorem 97 of [Suppes] p. 89.
|
| ⊢
A ∈ V
& ⊢ B ∈ V |