![]() |
Metamath
Proof Explorer Theorem List (p. 80 of 481) | < Previous Next > |
Bad symbols? Try the
GIF version. |
||
Mirrors > Metamath Home Page > MPE Home Page > Theorem List Contents > Recent Proofs This page: Page List |
Color key: | ![]() (1-30643) |
![]() (30644-32166) |
![]() (32167-48064) |
Type | Label | Description |
---|---|---|
Statement | ||
Theorem | imaex 7901 | The image of a set is a set. Theorem 3.17 of [Monk1] p. 39. (Contributed by JJ, 24-Sep-2021.) |
⊢ 𝐴 ∈ V ⇒ ⊢ (𝐴 “ 𝐵) ∈ V | ||
Theorem | exse2 7902 | Any set relation is set-like. (Contributed by Mario Carneiro, 22-Jun-2015.) |
⊢ (𝑅 ∈ 𝑉 → 𝑅 Se 𝐴) | ||
Theorem | xpexr 7903 | If a Cartesian product is a set, one of its components must be a set. (Contributed by NM, 27-Aug-2006.) |
⊢ ((𝐴 × 𝐵) ∈ 𝐶 → (𝐴 ∈ V ∨ 𝐵 ∈ V)) | ||
Theorem | xpexr2 7904 | If a nonempty Cartesian product is a set, so are both of its components. (Contributed by NM, 27-Aug-2006.) |
⊢ (((𝐴 × 𝐵) ∈ 𝐶 ∧ (𝐴 × 𝐵) ≠ ∅) → (𝐴 ∈ V ∧ 𝐵 ∈ V)) | ||
Theorem | xpexcnv 7905 | A condition where the converse of xpex 7734 holds as well. Corollary 6.9(2) in [TakeutiZaring] p. 26. (Contributed by Andrew Salmon, 13-Nov-2011.) |
⊢ ((𝐵 ≠ ∅ ∧ (𝐴 × 𝐵) ∈ V) → 𝐴 ∈ V) | ||
Theorem | soex 7906 | If the relation in a strict order is a set, then the base field is also a set. (Contributed by Mario Carneiro, 27-Apr-2015.) |
⊢ ((𝑅 Or 𝐴 ∧ 𝑅 ∈ 𝑉) → 𝐴 ∈ V) | ||
Theorem | elxp4 7907 | Membership in a Cartesian product. This version requires no quantifiers or dummy variables. See also elxp5 7908, elxp6 8003, and elxp7 8004. (Contributed by NM, 17-Feb-2004.) |
⊢ (𝐴 ∈ (𝐵 × 𝐶) ↔ (𝐴 = 〈∪ dom {𝐴}, ∪ ran {𝐴}〉 ∧ (∪ dom {𝐴} ∈ 𝐵 ∧ ∪ ran {𝐴} ∈ 𝐶))) | ||
Theorem | elxp5 7908 | Membership in a Cartesian product requiring no quantifiers or dummy variables. Provides a slightly shorter version of elxp4 7907 when the double intersection does not create class existence problems (caused by int0 4957). (Contributed by NM, 1-Aug-2004.) |
⊢ (𝐴 ∈ (𝐵 × 𝐶) ↔ (𝐴 = 〈∩ ∩ 𝐴, ∪ ran {𝐴}〉 ∧ (∩ ∩ 𝐴 ∈ 𝐵 ∧ ∪ ran {𝐴} ∈ 𝐶))) | ||
Theorem | cnvexg 7909 | The converse of a set is a set. Corollary 6.8(1) of [TakeutiZaring] p. 26. (Contributed by NM, 17-Mar-1998.) |
⊢ (𝐴 ∈ 𝑉 → ◡𝐴 ∈ V) | ||
Theorem | cnvex 7910 | The converse of a set is a set. Corollary 6.8(1) of [TakeutiZaring] p. 26. (Contributed by NM, 19-Dec-2003.) |
⊢ 𝐴 ∈ V ⇒ ⊢ ◡𝐴 ∈ V | ||
Theorem | relcnvexb 7911 | A relation is a set iff its converse is a set. (Contributed by FL, 3-Mar-2007.) |
⊢ (Rel 𝑅 → (𝑅 ∈ V ↔ ◡𝑅 ∈ V)) | ||
Theorem | f1oexrnex 7912 | If the range of a 1-1 onto function is a set, the function itself is a set. (Contributed by AV, 2-Jun-2019.) |
⊢ ((𝐹:𝐴–1-1-onto→𝐵 ∧ 𝐵 ∈ 𝑉) → 𝐹 ∈ V) | ||
Theorem | f1oexbi 7913* | There is a one-to-one onto function from a set to a second set iff there is a one-to-one onto function from the second set to the first set. (Contributed by Alexander van der Vekens, 30-Sep-2018.) |
⊢ (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 ↔ ∃𝑔 𝑔:𝐵–1-1-onto→𝐴) | ||
Theorem | coexg 7914 | The composition of two sets is a set. (Contributed by NM, 19-Mar-1998.) |
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (𝐴 ∘ 𝐵) ∈ V) | ||
Theorem | coex 7915 | The composition of two sets is a set. (Contributed by NM, 15-Dec-2003.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V ⇒ ⊢ (𝐴 ∘ 𝐵) ∈ V | ||
Theorem | funcnvuni 7916* | The union of a chain (with respect to inclusion) of single-rooted sets is single-rooted. (See funcnv 6608 for "single-rooted" definition.) (Contributed by NM, 11-Aug-2004.) |
⊢ (∀𝑓 ∈ 𝐴 (Fun ◡𝑓 ∧ ∀𝑔 ∈ 𝐴 (𝑓 ⊆ 𝑔 ∨ 𝑔 ⊆ 𝑓)) → Fun ◡∪ 𝐴) | ||
Theorem | fun11uni 7917* | The union of a chain (with respect to inclusion) of one-to-one functions is a one-to-one function. (Contributed by NM, 11-Aug-2004.) |
⊢ (∀𝑓 ∈ 𝐴 ((Fun 𝑓 ∧ Fun ◡𝑓) ∧ ∀𝑔 ∈ 𝐴 (𝑓 ⊆ 𝑔 ∨ 𝑔 ⊆ 𝑓)) → (Fun ∪ 𝐴 ∧ Fun ◡∪ 𝐴)) | ||
Theorem | fex2 7918 | A function with bounded domain and codomain is a set. This version of fex 7220 is proven without the Axiom of Replacement ax-rep 5276, but depends on ax-un 7719, which is not required for the proof of fex 7220. (Contributed by Mario Carneiro, 24-Jun-2015.) |
⊢ ((𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → 𝐹 ∈ V) | ||
Theorem | fabexg 7919* | Existence of a set of functions. (Contributed by Paul Chapman, 25-Feb-2008.) |
⊢ 𝐹 = {𝑥 ∣ (𝑥:𝐴⟶𝐵 ∧ 𝜑)} ⇒ ⊢ ((𝐴 ∈ 𝐶 ∧ 𝐵 ∈ 𝐷) → 𝐹 ∈ V) | ||
Theorem | fabex 7920* | Existence of a set of functions. (Contributed by NM, 3-Dec-2007.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V & ⊢ 𝐹 = {𝑥 ∣ (𝑥:𝐴⟶𝐵 ∧ 𝜑)} ⇒ ⊢ 𝐹 ∈ V | ||
Theorem | f1oabexg 7921* | The class of all 1-1-onto functions mapping one set to another is a set. (Contributed by Paul Chapman, 25-Feb-2008.) |
⊢ 𝐹 = {𝑓 ∣ (𝑓:𝐴–1-1-onto→𝐵 ∧ 𝜑)} ⇒ ⊢ ((𝐴 ∈ 𝐶 ∧ 𝐵 ∈ 𝐷) → 𝐹 ∈ V) | ||
Theorem | fiunlem 7922* | Lemma for fiun 7923 and f1iun 7924. Formerly part of f1iun 7924. (Contributed by AV, 6-Oct-2023.) |
⊢ (𝑥 = 𝑦 → 𝐵 = 𝐶) ⇒ ⊢ (((𝐵:𝐷⟶𝑆 ∧ ∀𝑦 ∈ 𝐴 (𝐵 ⊆ 𝐶 ∨ 𝐶 ⊆ 𝐵)) ∧ 𝑢 = 𝐵) → ∀𝑣 ∈ {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = 𝐵} (𝑢 ⊆ 𝑣 ∨ 𝑣 ⊆ 𝑢)) | ||
Theorem | fiun 7923* | The union of a chain (with respect to inclusion) of functions is a function. Analogous to f1iun 7924. (Contributed by AV, 6-Oct-2023.) |
⊢ (𝑥 = 𝑦 → 𝐵 = 𝐶) & ⊢ 𝐵 ∈ V ⇒ ⊢ (∀𝑥 ∈ 𝐴 (𝐵:𝐷⟶𝑆 ∧ ∀𝑦 ∈ 𝐴 (𝐵 ⊆ 𝐶 ∨ 𝐶 ⊆ 𝐵)) → ∪ 𝑥 ∈ 𝐴 𝐵:∪ 𝑥 ∈ 𝐴 𝐷⟶𝑆) | ||
Theorem | f1iun 7924* | The union of a chain (with respect to inclusion) of one-to-one functions is a one-to-one function. (Contributed by Mario Carneiro, 20-May-2013.) (Revised by Mario Carneiro, 24-Jun-2015.) (Proof shortened by AV, 5-Nov-2023.) |
⊢ (𝑥 = 𝑦 → 𝐵 = 𝐶) & ⊢ 𝐵 ∈ V ⇒ ⊢ (∀𝑥 ∈ 𝐴 (𝐵:𝐷–1-1→𝑆 ∧ ∀𝑦 ∈ 𝐴 (𝐵 ⊆ 𝐶 ∨ 𝐶 ⊆ 𝐵)) → ∪ 𝑥 ∈ 𝐴 𝐵:∪ 𝑥 ∈ 𝐴 𝐷–1-1→𝑆) | ||
Theorem | fviunfun 7925* | The function value of an indexed union is the value of one of the indexed functions. (Contributed by AV, 4-Nov-2023.) |
⊢ 𝑈 = ∪ 𝑖 ∈ 𝐼 (𝐹‘𝑖) ⇒ ⊢ ((Fun 𝑈 ∧ 𝐽 ∈ 𝐼 ∧ 𝑋 ∈ dom (𝐹‘𝐽)) → (𝑈‘𝑋) = ((𝐹‘𝐽)‘𝑋)) | ||
Theorem | ffoss 7926* | Relationship between a mapping and an onto mapping. Figure 38 of [Enderton] p. 145. (Contributed by NM, 10-May-1998.) |
⊢ 𝐹 ∈ V ⇒ ⊢ (𝐹:𝐴⟶𝐵 ↔ ∃𝑥(𝐹:𝐴–onto→𝑥 ∧ 𝑥 ⊆ 𝐵)) | ||
Theorem | f11o 7927* | Relationship between one-to-one and one-to-one onto function. (Contributed by NM, 4-Apr-1998.) |
⊢ 𝐹 ∈ V ⇒ ⊢ (𝐹:𝐴–1-1→𝐵 ↔ ∃𝑥(𝐹:𝐴–1-1-onto→𝑥 ∧ 𝑥 ⊆ 𝐵)) | ||
Theorem | resfunexgALT 7928 | Alternate proof of resfunexg 7209, shorter but requiring ax-pow 5354 and ax-un 7719. (Contributed by NM, 7-Apr-1995.) (Proof modification is discouraged.) (New usage is discouraged.) |
⊢ ((Fun 𝐴 ∧ 𝐵 ∈ 𝐶) → (𝐴 ↾ 𝐵) ∈ V) | ||
Theorem | cofunexg 7929 | Existence of a composition when the first member is a function. (Contributed by NM, 8-Oct-2007.) |
⊢ ((Fun 𝐴 ∧ 𝐵 ∈ 𝐶) → (𝐴 ∘ 𝐵) ∈ V) | ||
Theorem | cofunex2g 7930 | Existence of a composition when the second member is one-to-one. (Contributed by NM, 8-Oct-2007.) |
⊢ ((𝐴 ∈ 𝑉 ∧ Fun ◡𝐵) → (𝐴 ∘ 𝐵) ∈ V) | ||
Theorem | fnexALT 7931 | Alternate proof of fnex 7211, derived using the Axiom of Replacement in the form of funimaexg 6625. This version uses ax-pow 5354 and ax-un 7719, whereas fnex 7211 does not. (Contributed by NM, 14-Aug-1994.) (Proof modification is discouraged.) (New usage is discouraged.) |
⊢ ((𝐹 Fn 𝐴 ∧ 𝐴 ∈ 𝐵) → 𝐹 ∈ V) | ||
Theorem | funexw 7932 | Weak version of funex 7213 that holds without ax-rep 5276. If the domain and codomain of a function exist, so does the function. (Contributed by Rohan Ridenour, 13-Aug-2023.) |
⊢ ((Fun 𝐹 ∧ dom 𝐹 ∈ 𝐵 ∧ ran 𝐹 ∈ 𝐶) → 𝐹 ∈ V) | ||
Theorem | mptexw 7933* | Weak version of mptex 7217 that holds without ax-rep 5276. If the domain and codomain of a function given by maps-to notation are sets, the function is a set. (Contributed by Rohan Ridenour, 13-Aug-2023.) |
⊢ 𝐴 ∈ V & ⊢ 𝐶 ∈ V & ⊢ ∀𝑥 ∈ 𝐴 𝐵 ∈ 𝐶 ⇒ ⊢ (𝑥 ∈ 𝐴 ↦ 𝐵) ∈ V | ||
Theorem | funrnex 7934 | If the domain of a function exists, so does its range. Part of Theorem 4.15(v) of [Monk1] p. 46. This theorem is derived using the Axiom of Replacement in the form of funex 7213. (Contributed by NM, 11-Nov-1995.) |
⊢ (dom 𝐹 ∈ 𝐵 → (Fun 𝐹 → ran 𝐹 ∈ V)) | ||
Theorem | zfrep6 7935* | A version of the Axiom of Replacement. Normally 𝜑 would have free variables 𝑥 and 𝑦. Axiom 6 of [Kunen] p. 12. The Separation Scheme ax-sep 5290 cannot be derived from this version and must be stated as a separate axiom in an axiom system (such as Kunen's) that uses this version in place of our ax-rep 5276. (Contributed by NM, 10-Oct-2003.) |
⊢ (∀𝑥 ∈ 𝑧 ∃!𝑦𝜑 → ∃𝑤∀𝑥 ∈ 𝑧 ∃𝑦 ∈ 𝑤 𝜑) | ||
Theorem | focdmex 7936 | If the domain of an onto function exists, so does its codomain. (Contributed by NM, 23-Jul-2004.) |
⊢ (𝐴 ∈ 𝐶 → (𝐹:𝐴–onto→𝐵 → 𝐵 ∈ V)) | ||
Theorem | f1dmex 7937 | If the codomain of a one-to-one function exists, so does its domain. This theorem is equivalent to the Axiom of Replacement ax-rep 5276. (Contributed by NM, 4-Sep-2004.) |
⊢ ((𝐹:𝐴–1-1→𝐵 ∧ 𝐵 ∈ 𝐶) → 𝐴 ∈ V) | ||
Theorem | f1ovv 7938 | The codomain/range of a 1-1 onto function is a set iff its domain is a set. (Contributed by AV, 21-Mar-2019.) |
⊢ (𝐹:𝐴–1-1-onto→𝐵 → (𝐴 ∈ V ↔ 𝐵 ∈ V)) | ||
Theorem | fvclex 7939* | Existence of the class of values of a set. (Contributed by NM, 9-Nov-1995.) |
⊢ 𝐹 ∈ V ⇒ ⊢ {𝑦 ∣ ∃𝑥 𝑦 = (𝐹‘𝑥)} ∈ V | ||
Theorem | fvresex 7940* | Existence of the class of values of a restricted class. (Contributed by NM, 14-Nov-1995.) (Revised by Mario Carneiro, 11-Sep-2015.) |
⊢ 𝐴 ∈ V ⇒ ⊢ {𝑦 ∣ ∃𝑥 𝑦 = ((𝐹 ↾ 𝐴)‘𝑥)} ∈ V | ||
Theorem | abrexexg 7941* | Existence of a class abstraction of existentially restricted sets. The class 𝐵 can be thought of as an expression in 𝑥 (which is typically a free variable in the class expression substituted for 𝐵) and the class abstraction appearing in the statement as the class of values 𝐵 as 𝑥 varies through 𝐴. If the "domain" 𝐴 is a set, then the abstraction is also a set. Therefore, this statement is a kind of Replacement. This can be seen by tracing back through the path axrep6g 5284, axrep6 5283, ax-rep 5276. See also abrexex2g 7945. There are partial converses under additional conditions, see for instance abnexg 7737. (Contributed by NM, 3-Nov-2003.) (Proof shortened by Mario Carneiro, 31-Aug-2015.) Avoid ax-10 2129, ax-11 2146, ax-12 2163, ax-pr 5418, ax-un 7719 and shorten proof. (Revised by SN, 11-Dec-2024.) |
⊢ (𝐴 ∈ 𝑉 → {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝑦 = 𝐵} ∈ V) | ||
Theorem | abrexexgOLD 7942* |
Obsolete version of abrexexg 7941 as of 11-Dec-2024. EDITORIAL: Comment
kept since the line of equivalences to ax-rep 5276 is different.
Existence of a class abstraction of existentially restricted sets. The class 𝐵 can be thought of as an expression in 𝑥 (which is typically a free variable in the class expression substituted for 𝐵) and the class abstraction appearing in the statement as the class of values 𝐵 as 𝑥 varies through 𝐴. If the "domain" 𝐴 is a set, then the abstraction is also a set. Therefore, this statement is a kind of Replacement. This can be seen by tracing back through the path mptexg 7215, funex 7213, fnex 7211, resfunexg 7209, and funimaexg 6625. See also abrexex2g 7945. There are partial converses under additional conditions, see for instance abnexg 7737. (Contributed by NM, 3-Nov-2003.) (Proof shortened by Mario Carneiro, 31-Aug-2015.) (Proof modification is discouraged.) (New usage is discouraged.) |
⊢ (𝐴 ∈ 𝑉 → {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝑦 = 𝐵} ∈ V) | ||
Theorem | abrexex 7943* | Existence of a class abstraction of existentially restricted sets. See the comment of abrexexg 7941. See also abrexex2 7950. (Contributed by NM, 16-Oct-2003.) (Proof shortened by Mario Carneiro, 31-Aug-2015.) |
⊢ 𝐴 ∈ V ⇒ ⊢ {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝑦 = 𝐵} ∈ V | ||
Theorem | iunexg 7944* | The existence of an indexed union. 𝑥 is normally a free-variable parameter in 𝐵. (Contributed by NM, 23-Mar-2006.) |
⊢ ((𝐴 ∈ 𝑉 ∧ ∀𝑥 ∈ 𝐴 𝐵 ∈ 𝑊) → ∪ 𝑥 ∈ 𝐴 𝐵 ∈ V) | ||
Theorem | abrexex2g 7945* | Existence of an existentially restricted class abstraction. (Contributed by Jeff Madsen, 2-Sep-2009.) |
⊢ ((𝐴 ∈ 𝑉 ∧ ∀𝑥 ∈ 𝐴 {𝑦 ∣ 𝜑} ∈ 𝑊) → {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝜑} ∈ V) | ||
Theorem | opabex3d 7946* | Existence of an ordered pair abstraction, deduction version. (Contributed by Alexander van der Vekens, 19-Oct-2017.) (Revised by AV, 9-Aug-2024.) |
⊢ (𝜑 → 𝐴 ∈ 𝑉) & ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → {𝑦 ∣ 𝜓} ∈ V) ⇒ ⊢ (𝜑 → {〈𝑥, 𝑦〉 ∣ (𝑥 ∈ 𝐴 ∧ 𝜓)} ∈ V) | ||
Theorem | opabex3rd 7947* | Existence of an ordered pair abstraction if the second components are elements of a set. (Contributed by AV, 17-Sep-2023.) (Revised by AV, 9-Aug-2024.) |
⊢ (𝜑 → 𝐴 ∈ 𝑉) & ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐴) → {𝑥 ∣ 𝜓} ∈ V) ⇒ ⊢ (𝜑 → {〈𝑥, 𝑦〉 ∣ (𝑦 ∈ 𝐴 ∧ 𝜓)} ∈ V) | ||
Theorem | opabex3 7948* | Existence of an ordered pair abstraction. (Contributed by Jeff Madsen, 2-Sep-2009.) |
⊢ 𝐴 ∈ V & ⊢ (𝑥 ∈ 𝐴 → {𝑦 ∣ 𝜑} ∈ V) ⇒ ⊢ {〈𝑥, 𝑦〉 ∣ (𝑥 ∈ 𝐴 ∧ 𝜑)} ∈ V | ||
Theorem | iunex 7949* | The existence of an indexed union. 𝑥 is normally a free-variable parameter in the class expression substituted for 𝐵, which can be read informally as 𝐵(𝑥). (Contributed by NM, 13-Oct-2003.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V ⇒ ⊢ ∪ 𝑥 ∈ 𝐴 𝐵 ∈ V | ||
Theorem | abrexex2 7950* | Existence of an existentially restricted class abstraction. 𝜑 normally has free-variable parameters 𝑥 and 𝑦. See also abrexex 7943. (Contributed by NM, 12-Sep-2004.) |
⊢ 𝐴 ∈ V & ⊢ {𝑦 ∣ 𝜑} ∈ V ⇒ ⊢ {𝑦 ∣ ∃𝑥 ∈ 𝐴 𝜑} ∈ V | ||
Theorem | abexssex 7951* | Existence of a class abstraction with an existentially quantified expression. Both 𝑥 and 𝑦 can be free in 𝜑. (Contributed by NM, 29-Jul-2006.) |
⊢ 𝐴 ∈ V & ⊢ {𝑦 ∣ 𝜑} ∈ V ⇒ ⊢ {𝑦 ∣ ∃𝑥(𝑥 ⊆ 𝐴 ∧ 𝜑)} ∈ V | ||
Theorem | abexex 7952* | A condition where a class abstraction continues to exist after its wff is existentially quantified. (Contributed by NM, 4-Mar-2007.) |
⊢ 𝐴 ∈ V & ⊢ (𝜑 → 𝑥 ∈ 𝐴) & ⊢ {𝑦 ∣ 𝜑} ∈ V ⇒ ⊢ {𝑦 ∣ ∃𝑥𝜑} ∈ V | ||
Theorem | f1oweALT 7953* | Alternate proof of f1owe 7343, more direct since not using the isomorphism predicate, but requiring ax-un 7719. (Contributed by NM, 4-Mar-1997.) (Proof modification is discouraged.) (New usage is discouraged.) |
⊢ 𝑅 = {〈𝑥, 𝑦〉 ∣ (𝐹‘𝑥)𝑆(𝐹‘𝑦)} ⇒ ⊢ (𝐹:𝐴–1-1-onto→𝐵 → (𝑆 We 𝐵 → 𝑅 We 𝐴)) | ||
Theorem | wemoiso 7954* | Thus, there is at most one isomorphism between any two well-ordered sets. TODO: Shorten finnisoeu 10105. (Contributed by Stefan O'Rear, 12-Feb-2015.) (Revised by Mario Carneiro, 25-Jun-2015.) |
⊢ (𝑅 We 𝐴 → ∃*𝑓 𝑓 Isom 𝑅, 𝑆 (𝐴, 𝐵)) | ||
Theorem | wemoiso2 7955* | Thus, there is at most one isomorphism between any two well-ordered sets. (Contributed by Stefan O'Rear, 12-Feb-2015.) (Revised by Mario Carneiro, 25-Jun-2015.) |
⊢ (𝑆 We 𝐵 → ∃*𝑓 𝑓 Isom 𝑅, 𝑆 (𝐴, 𝐵)) | ||
Theorem | oprabexd 7956* | Existence of an operator abstraction. (Contributed by Jeff Madsen, 2-Sep-2009.) (Revised by AV, 9-Aug-2024.) |
⊢ (𝜑 → 𝐴 ∈ 𝑉) & ⊢ (𝜑 → 𝐵 ∈ 𝑊) & ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → ∃*𝑧𝜓) & ⊢ (𝜑 → 𝐹 = {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) ∧ 𝜓)}) ⇒ ⊢ (𝜑 → 𝐹 ∈ V) | ||
Theorem | oprabex 7957* | Existence of an operation class abstraction. (Contributed by NM, 19-Oct-2004.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V & ⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → ∃*𝑧𝜑) & ⊢ 𝐹 = {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) ∧ 𝜑)} ⇒ ⊢ 𝐹 ∈ V | ||
Theorem | oprabex3 7958* | Existence of an operation class abstraction (special case). (Contributed by NM, 19-Oct-2004.) |
⊢ 𝐻 ∈ V & ⊢ 𝐹 = {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ ((𝑥 ∈ (𝐻 × 𝐻) ∧ 𝑦 ∈ (𝐻 × 𝐻)) ∧ ∃𝑤∃𝑣∃𝑢∃𝑓((𝑥 = 〈𝑤, 𝑣〉 ∧ 𝑦 = 〈𝑢, 𝑓〉) ∧ 𝑧 = 𝑅))} ⇒ ⊢ 𝐹 ∈ V | ||
Theorem | oprabrexex2 7959* | Existence of an existentially restricted operation abstraction. (Contributed by Jeff Madsen, 11-Jun-2010.) |
⊢ 𝐴 ∈ V & ⊢ {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ 𝜑} ∈ V ⇒ ⊢ {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ ∃𝑤 ∈ 𝐴 𝜑} ∈ V | ||
Theorem | ab2rexex 7960* | Existence of a class abstraction of existentially restricted sets. Variables 𝑥 and 𝑦 are normally free-variable parameters in the class expression substituted for 𝐶, which can be thought of as 𝐶(𝑥, 𝑦). See comments for abrexex 7943. (Contributed by NM, 20-Sep-2011.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V ⇒ ⊢ {𝑧 ∣ ∃𝑥 ∈ 𝐴 ∃𝑦 ∈ 𝐵 𝑧 = 𝐶} ∈ V | ||
Theorem | ab2rexex2 7961* | Existence of an existentially restricted class abstraction. 𝜑 normally has free-variable parameters 𝑥, 𝑦, and 𝑧. Compare abrexex2 7950. (Contributed by NM, 20-Sep-2011.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V & ⊢ {𝑧 ∣ 𝜑} ∈ V ⇒ ⊢ {𝑧 ∣ ∃𝑥 ∈ 𝐴 ∃𝑦 ∈ 𝐵 𝜑} ∈ V | ||
Theorem | xpexgALT 7962 | Alternate proof of xpexg 7731 requiring Replacement (ax-rep 5276) but not Power Set (ax-pow 5354). (Contributed by Mario Carneiro, 20-May-2013.) (Proof modification is discouraged.) (New usage is discouraged.) |
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (𝐴 × 𝐵) ∈ V) | ||
Theorem | offval3 7963* | General value of (𝐹 ∘f 𝑅𝐺) with no assumptions on functionality of 𝐹 and 𝐺. (Contributed by Stefan O'Rear, 24-Jan-2015.) |
⊢ ((𝐹 ∈ 𝑉 ∧ 𝐺 ∈ 𝑊) → (𝐹 ∘f 𝑅𝐺) = (𝑥 ∈ (dom 𝐹 ∩ dom 𝐺) ↦ ((𝐹‘𝑥)𝑅(𝐺‘𝑥)))) | ||
Theorem | offres 7964 | Pointwise combination commutes with restriction. (Contributed by Stefan O'Rear, 24-Jan-2015.) |
⊢ ((𝐹 ∈ 𝑉 ∧ 𝐺 ∈ 𝑊) → ((𝐹 ∘f 𝑅𝐺) ↾ 𝐷) = ((𝐹 ↾ 𝐷) ∘f 𝑅(𝐺 ↾ 𝐷))) | ||
Theorem | ofmres 7965* | Equivalent expressions for a restriction of the function operation map. Unlike ∘f 𝑅 which is a proper class, ( ∘f 𝑅 ↾ (𝐴 × 𝐵)) can be a set by ofmresex 7966, allowing it to be used as a function or structure argument. By ofmresval 7680, the restricted operation map values are the same as the original values, allowing theorems for ∘f 𝑅 to be reused. (Contributed by NM, 20-Oct-2014.) |
⊢ ( ∘f 𝑅 ↾ (𝐴 × 𝐵)) = (𝑓 ∈ 𝐴, 𝑔 ∈ 𝐵 ↦ (𝑓 ∘f 𝑅𝑔)) | ||
Theorem | ofmresex 7966 | Existence of a restriction of the function operation map. (Contributed by NM, 20-Oct-2014.) |
⊢ (𝜑 → 𝐴 ∈ 𝑉) & ⊢ (𝜑 → 𝐵 ∈ 𝑊) ⇒ ⊢ (𝜑 → ( ∘f 𝑅 ↾ (𝐴 × 𝐵)) ∈ V) | ||
Syntax | c1st 7967 | Extend the definition of a class to include the first member an ordered pair function. |
class 1st | ||
Syntax | c2nd 7968 | Extend the definition of a class to include the second member an ordered pair function. |
class 2nd | ||
Definition | df-1st 7969 | Define a function that extracts the first member, or abscissa, of an ordered pair. Theorem op1st 7977 proves that it does this. For example, (1st ‘〈3, 4〉) = 3. Equivalent to Definition 5.13 (i) of [Monk1] p. 52 (compare op1sta 6215 and op1stb 5462). The notation is the same as Monk's. (Contributed by NM, 9-Oct-2004.) |
⊢ 1st = (𝑥 ∈ V ↦ ∪ dom {𝑥}) | ||
Definition | df-2nd 7970 | Define a function that extracts the second member, or ordinate, of an ordered pair. Theorem op2nd 7978 proves that it does this. For example, (2nd ‘〈3, 4〉) = 4. Equivalent to Definition 5.13 (ii) of [Monk1] p. 52 (compare op2nda 6218 and op2ndb 6217). The notation is the same as Monk's. (Contributed by NM, 9-Oct-2004.) |
⊢ 2nd = (𝑥 ∈ V ↦ ∪ ran {𝑥}) | ||
Theorem | 1stval 7971 | The value of the function that extracts the first member of an ordered pair. (Contributed by NM, 9-Oct-2004.) (Revised by Mario Carneiro, 8-Sep-2013.) |
⊢ (1st ‘𝐴) = ∪ dom {𝐴} | ||
Theorem | 2ndval 7972 | The value of the function that extracts the second member of an ordered pair. (Contributed by NM, 9-Oct-2004.) (Revised by Mario Carneiro, 8-Sep-2013.) |
⊢ (2nd ‘𝐴) = ∪ ran {𝐴} | ||
Theorem | 1stnpr 7973 | Value of the first-member function at non-pairs. (Contributed by Thierry Arnoux, 22-Sep-2017.) |
⊢ (¬ 𝐴 ∈ (V × V) → (1st ‘𝐴) = ∅) | ||
Theorem | 2ndnpr 7974 | Value of the second-member function at non-pairs. (Contributed by Thierry Arnoux, 22-Sep-2017.) |
⊢ (¬ 𝐴 ∈ (V × V) → (2nd ‘𝐴) = ∅) | ||
Theorem | 1st0 7975 | The value of the first-member function at the empty set. (Contributed by NM, 23-Apr-2007.) |
⊢ (1st ‘∅) = ∅ | ||
Theorem | 2nd0 7976 | The value of the second-member function at the empty set. (Contributed by NM, 23-Apr-2007.) |
⊢ (2nd ‘∅) = ∅ | ||
Theorem | op1st 7977 | Extract the first member of an ordered pair. (Contributed by NM, 5-Oct-2004.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V ⇒ ⊢ (1st ‘〈𝐴, 𝐵〉) = 𝐴 | ||
Theorem | op2nd 7978 | Extract the second member of an ordered pair. (Contributed by NM, 5-Oct-2004.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V ⇒ ⊢ (2nd ‘〈𝐴, 𝐵〉) = 𝐵 | ||
Theorem | op1std 7979 | Extract the first member of an ordered pair. (Contributed by Mario Carneiro, 31-Aug-2015.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V ⇒ ⊢ (𝐶 = 〈𝐴, 𝐵〉 → (1st ‘𝐶) = 𝐴) | ||
Theorem | op2ndd 7980 | Extract the second member of an ordered pair. (Contributed by Mario Carneiro, 31-Aug-2015.) |
⊢ 𝐴 ∈ V & ⊢ 𝐵 ∈ V ⇒ ⊢ (𝐶 = 〈𝐴, 𝐵〉 → (2nd ‘𝐶) = 𝐵) | ||
Theorem | op1stg 7981 | Extract the first member of an ordered pair. (Contributed by NM, 19-Jul-2005.) |
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (1st ‘〈𝐴, 𝐵〉) = 𝐴) | ||
Theorem | op2ndg 7982 | Extract the second member of an ordered pair. (Contributed by NM, 19-Jul-2005.) |
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (2nd ‘〈𝐴, 𝐵〉) = 𝐵) | ||
Theorem | ot1stg 7983 | Extract the first member of an ordered triple. (Due to infrequent usage, it isn't worthwhile at this point to define special extractors for triples, so we reuse the ordered pair extractors for ot1stg 7983, ot2ndg 7984, ot3rdg 7985.) (Contributed by NM, 3-Apr-2015.) (Revised by Mario Carneiro, 2-May-2015.) |
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ∧ 𝐶 ∈ 𝑋) → (1st ‘(1st ‘〈𝐴, 𝐵, 𝐶〉)) = 𝐴) | ||
Theorem | ot2ndg 7984 | Extract the second member of an ordered triple. (See ot1stg 7983 comment.) (Contributed by NM, 3-Apr-2015.) (Revised by Mario Carneiro, 2-May-2015.) |
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊 ∧ 𝐶 ∈ 𝑋) → (2nd ‘(1st ‘〈𝐴, 𝐵, 𝐶〉)) = 𝐵) | ||
Theorem | ot3rdg 7985 | Extract the third member of an ordered triple. (See ot1stg 7983 comment.) (Contributed by NM, 3-Apr-2015.) |
⊢ (𝐶 ∈ 𝑉 → (2nd ‘〈𝐴, 𝐵, 𝐶〉) = 𝐶) | ||
Theorem | 1stval2 7986 | Alternate value of the function that extracts the first member of an ordered pair. Definition 5.13 (i) of [Monk1] p. 52. (Contributed by NM, 18-Aug-2006.) |
⊢ (𝐴 ∈ (V × V) → (1st ‘𝐴) = ∩ ∩ 𝐴) | ||
Theorem | 2ndval2 7987 | Alternate value of the function that extracts the second member of an ordered pair. Definition 5.13 (ii) of [Monk1] p. 52. (Contributed by NM, 18-Aug-2006.) |
⊢ (𝐴 ∈ (V × V) → (2nd ‘𝐴) = ∩ ∩ ∩ ◡{𝐴}) | ||
Theorem | oteqimp 7988 | The components of an ordered triple. (Contributed by Alexander van der Vekens, 2-Mar-2018.) |
⊢ (𝑇 = 〈𝐴, 𝐵, 𝐶〉 → ((𝐴 ∈ 𝑋 ∧ 𝐵 ∈ 𝑌 ∧ 𝐶 ∈ 𝑍) → ((1st ‘(1st ‘𝑇)) = 𝐴 ∧ (2nd ‘(1st ‘𝑇)) = 𝐵 ∧ (2nd ‘𝑇) = 𝐶))) | ||
Theorem | fo1st 7989 | The 1st function maps the universe onto the universe. (Contributed by NM, 14-Oct-2004.) (Revised by Mario Carneiro, 8-Sep-2013.) |
⊢ 1st :V–onto→V | ||
Theorem | fo2nd 7990 | The 2nd function maps the universe onto the universe. (Contributed by NM, 14-Oct-2004.) (Revised by Mario Carneiro, 8-Sep-2013.) |
⊢ 2nd :V–onto→V | ||
Theorem | br1steqg 7991 | Uniqueness condition for the binary relation 1st. (Contributed by Scott Fenton, 2-Jul-2020.) Revised to remove sethood hypothesis on 𝐶. (Revised by Peter Mazsa, 17-Jan-2022.) |
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (〈𝐴, 𝐵〉1st 𝐶 ↔ 𝐶 = 𝐴)) | ||
Theorem | br2ndeqg 7992 | Uniqueness condition for the binary relation 2nd. (Contributed by Scott Fenton, 2-Jul-2020.) Revised to remove sethood hypothesis on 𝐶. (Revised by Peter Mazsa, 17-Jan-2022.) |
⊢ ((𝐴 ∈ 𝑉 ∧ 𝐵 ∈ 𝑊) → (〈𝐴, 𝐵〉2nd 𝐶 ↔ 𝐶 = 𝐵)) | ||
Theorem | f1stres 7993 | Mapping of a restriction of the 1st (first member of an ordered pair) function. (Contributed by NM, 11-Oct-2004.) (Revised by Mario Carneiro, 8-Sep-2013.) |
⊢ (1st ↾ (𝐴 × 𝐵)):(𝐴 × 𝐵)⟶𝐴 | ||
Theorem | f2ndres 7994 | Mapping of a restriction of the 2nd (second member of an ordered pair) function. (Contributed by NM, 7-Aug-2006.) (Revised by Mario Carneiro, 8-Sep-2013.) |
⊢ (2nd ↾ (𝐴 × 𝐵)):(𝐴 × 𝐵)⟶𝐵 | ||
Theorem | fo1stres 7995 | Onto mapping of a restriction of the 1st (first member of an ordered pair) function. (Contributed by NM, 14-Dec-2008.) |
⊢ (𝐵 ≠ ∅ → (1st ↾ (𝐴 × 𝐵)):(𝐴 × 𝐵)–onto→𝐴) | ||
Theorem | fo2ndres 7996 | Onto mapping of a restriction of the 2nd (second member of an ordered pair) function. (Contributed by NM, 14-Dec-2008.) |
⊢ (𝐴 ≠ ∅ → (2nd ↾ (𝐴 × 𝐵)):(𝐴 × 𝐵)–onto→𝐵) | ||
Theorem | 1st2val 7997* | Value of an alternate definition of the 1st function. (Contributed by NM, 14-Oct-2004.) (Revised by Mario Carneiro, 30-Dec-2014.) |
⊢ ({〈〈𝑥, 𝑦〉, 𝑧〉 ∣ 𝑧 = 𝑥}‘𝐴) = (1st ‘𝐴) | ||
Theorem | 2nd2val 7998* | Value of an alternate definition of the 2nd function. (Contributed by NM, 10-Aug-2006.) (Revised by Mario Carneiro, 30-Dec-2014.) |
⊢ ({〈〈𝑥, 𝑦〉, 𝑧〉 ∣ 𝑧 = 𝑦}‘𝐴) = (2nd ‘𝐴) | ||
Theorem | 1stcof 7999 | Composition of the first member function with another function. (Contributed by NM, 12-Oct-2007.) |
⊢ (𝐹:𝐴⟶(𝐵 × 𝐶) → (1st ∘ 𝐹):𝐴⟶𝐵) | ||
Theorem | 2ndcof 8000 | Composition of the second member function with another function. (Contributed by FL, 15-Oct-2012.) |
⊢ (𝐹:𝐴⟶(𝐵 × 𝐶) → (2nd ∘ 𝐹):𝐴⟶𝐶) |
< Previous Next > |
Copyright terms: Public domain | < Previous Next > |