HomeHome Metamath Proof Explorer < Previous   Next >
Related theorems
Unicode version

Definition df-2nd 4080
Description: Define a function that extracts the second member of an ordered pair. Theorem op2nd 4086 proves that it does this. Equivalent to Definition 5.13 (ii) of [Monk1] p. 52 (compare op2nda 3452 and op2ndb 3451). The notation is the same as Monk's.
Assertion
Ref Expression
df-2nd |- 2nd = {<.x, y>. | y = U.ran { x}}
Distinct variable group:   x,y

Detailed syntax breakdown of Definition df-2nd
StepHypRef Expression
1 c2nd 4078 . 2 class 2nd
2 vy . . . . 5 set y
32cv 955 . . . 4 class y
4 vx . . . . . . . 8 set x
54cv 955 . . . . . . 7 class x
65csn 2409 . . . . . 6 class {x}
76crn 3171 . . . . 5 class ran { x}
87cuni 2503 . . . 4 class U.ran { x}
93, 8wceq 956 . . 3 wff y = U.ran { x}
109, 4, 2copab 2666 . 2 class {<.x, y>. | y = U.ran { x}}
111, 10wceq 956 1 wff 2nd = {<.x, y>. | y = U.ran { x}}
Colors of variables: wff set class
This definition is referenced by:  2ndval 4082  fo2nd 4092  f2ndres 4094
Copyright terms: Public domain