Metamath Proof Explorer


Theorem ee020

Description: e020 without virtual deductions. (Contributed by Alan Sare, 13-Jul-2011) (Proof modification is discouraged.) (New usage is discouraged.)

Ref Expression
Hypotheses ee020.1 φ
ee020.2 ψχθ
ee020.3 τ
ee020.4 φθτη
Assertion ee020 ψχη

Proof

Step Hyp Ref Expression
1 ee020.1 φ
2 ee020.2 ψχθ
3 ee020.3 τ
4 ee020.4 φθτη
5 1 a1i χφ
6 5 a1i ψχφ
7 3 a1i χτ
8 7 a1i ψχτ
9 6 2 8 4 ee222 ψχη