Metamath Proof Explorer


Theorem leoptr

Description: The positive operator ordering relation is transitive. Exercise 1(iv) of Retherford p. 49. (Contributed by NM, 25-Jul-2006) (New usage is discouraged.)

Ref Expression
Assertion leoptr S HrmOp T HrmOp U HrmOp S op T T op U S op U

Proof

Step Hyp Ref Expression
1 r19.26 x S x ih x T x ih x T x ih x U x ih x x S x ih x T x ih x x T x ih x U x ih x
2 hmopre S HrmOp x S x ih x
3 hmopre T HrmOp x T x ih x
4 hmopre U HrmOp x U x ih x
5 letr S x ih x T x ih x U x ih x S x ih x T x ih x T x ih x U x ih x S x ih x U x ih x
6 2 3 4 5 syl3an S HrmOp x T HrmOp x U HrmOp x S x ih x T x ih x T x ih x U x ih x S x ih x U x ih x
7 6 3anandirs S HrmOp T HrmOp U HrmOp x S x ih x T x ih x T x ih x U x ih x S x ih x U x ih x
8 7 ralimdva S HrmOp T HrmOp U HrmOp x S x ih x T x ih x T x ih x U x ih x x S x ih x U x ih x
9 1 8 syl5bir S HrmOp T HrmOp U HrmOp x S x ih x T x ih x x T x ih x U x ih x x S x ih x U x ih x
10 leop2 S HrmOp T HrmOp S op T x S x ih x T x ih x
11 10 3adant3 S HrmOp T HrmOp U HrmOp S op T x S x ih x T x ih x
12 leop2 T HrmOp U HrmOp T op U x T x ih x U x ih x
13 12 3adant1 S HrmOp T HrmOp U HrmOp T op U x T x ih x U x ih x
14 11 13 anbi12d S HrmOp T HrmOp U HrmOp S op T T op U x S x ih x T x ih x x T x ih x U x ih x
15 leop2 S HrmOp U HrmOp S op U x S x ih x U x ih x
16 15 3adant2 S HrmOp T HrmOp U HrmOp S op U x S x ih x U x ih x
17 9 14 16 3imtr4d S HrmOp T HrmOp U HrmOp S op T T op U S op U
18 17 imp S HrmOp T HrmOp U HrmOp S op T T op U S op U