Metamath Proof Explorer


Theorem ralbidar

Description: More general form of ralbida . (Contributed by Andrew Salmon, 25-Jul-2011)

Ref Expression
Hypotheses ralbidar.1 φxAφ
ralbidar.2 φxAψχ
Assertion ralbidar φxAψxAχ

Proof

Step Hyp Ref Expression
1 ralbidar.1 φxAφ
2 ralbidar.2 φxAψχ
3 2 ex φxAψχ
4 3 ralimi xAφxAxAψχ
5 1 4 syl φxAxAψχ
6 df-ral xAxAψχxxAxAψχ
7 5 6 sylib φxxAxAψχ
8 pm2.43 xAxAψχxAψχ
9 8 pm5.74d xAxAψχxAψxAχ
10 9 alimi xxAxAψχxxAψxAχ
11 albi xxAψxAχxxAψxxAχ
12 7 10 11 3syl φxxAψxxAχ
13 df-ral xAψxxAψ
14 df-ral xAχxxAχ
15 12 13 14 3bitr4g φxAψxAχ