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Definition df-int 3927
 Description: Define the intersection of a class. Definition 7.35 of [TakeutiZaring] p. 44. For example, ∩{{ 1 , 3 }, { 1 , 8 }} = { 1 }. Compare this with the intersection of two classes, df-in 3213. (Contributed by NM, 18-Aug-1993.)
Assertion
Ref Expression
df-int A = {x y(y Ax y)}
Distinct variable group:   x,y,A

Detailed syntax breakdown of Definition df-int
StepHypRef Expression
1 cA . . 3 class A
21cint 3926 . 2 class A
3 vy . . . . . . 7 setvar y
43cv 1641 . . . . . 6 class y
54, 1wcel 1710 . . . . 5 wff y A
6 vx . . . . . 6 setvar x
76, 3wel 1711 . . . . 5 wff x y
85, 7wi 4 . . . 4 wff (y Ax y)
98, 3wal 1540 . . 3 wff y(y Ax y)
109, 6cab 2339 . 2 class {x y(y Ax y)}
112, 10wceq 1642 1 wff A = {x y(y Ax y)}
 Colors of variables: wff setvar class This definition is referenced by:  dfint2  3928  elint  3932  int0  3940  dfiin2g  4000
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