Metamath Proof Explorer


Definition df-ptdf

Description: Define the predicate PtDf , which is a utility definition used to shorten definitions and simplify proofs. (Contributed by Andrew Salmon, 15-Jul-2012)

Ref Expression
Assertion df-ptdf PtDf A B = x x v B - r A + v A 1 2 3

Detailed syntax breakdown

Step Hyp Ref Expression
0 cA class A
1 cB class B
2 0 1 cptdfc class PtDf A B
3 vx setvar x
4 cr class
5 3 cv setvar x
6 ctimesr class v
7 cminusr class - r
8 1 0 7 co class B - r A
9 5 8 6 co class x v B - r A
10 cpv class + v
11 9 0 10 co class x v B - r A + v A
12 c1 class 1
13 c2 class 2
14 c3 class 3
15 12 13 14 ctp class 1 2 3
16 11 15 cima class x v B - r A + v A 1 2 3
17 3 4 16 cmpt class x x v B - r A + v A 1 2 3
18 2 17 wceq wff PtDf A B = x x v B - r A + v A 1 2 3