Theorem 19.21bbi 1061

Description: Inference removing double quantifier.

Hypothesis

Ref	Expression
19.21bbi.1	|- (ph -> A.xA.yps)

Assertion

Ref	Expression
19.21bbi	|- (ph -> ps)

Proof of Theorem 19.21bbi

Step	Hyp	Ref	Expression
1		19.21bbi.1	. . 3 |- (ph -> A.xA.yps)
2	1	19.21bi 1060	. 2 |- (ph -> A.yps)
3	2	19.21bi 1060	1 |- (ph -> ps)

Syntax hints:   -> wi 3  A.wal 954

This theorem is referenced by:  trel 2687  pocl 2844  funun 3554  cmpmon 10743

This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-mp 7  ax-4 973

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