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Theorem sbimi 1762
Description: Infer substitution into antecedent and consequent of an implication. (Contributed by NM, 25-Jun-1998.)
Hypothesis
Ref Expression
sbimi.1  |-  ( ph  ->  ps )
Assertion
Ref Expression
sbimi  |-  ( [ y  /  x ] ph  ->  [ y  /  x ] ps )

Proof of Theorem sbimi
StepHypRef Expression
1 sbimi.1 . . . 4  |-  ( ph  ->  ps )
21imim2i 12 . . 3  |-  ( ( x  =  y  ->  ph )  ->  ( x  =  y  ->  ps ) )
31anim2i 342 . . . 4  |-  ( ( x  =  y  /\  ph )  ->  ( x  =  y  /\  ps )
)
43eximi 1598 . . 3  |-  ( E. x ( x  =  y  /\  ph )  ->  E. x ( x  =  y  /\  ps ) )
52, 4anim12i 338 . 2  |-  ( ( ( x  =  y  ->  ph )  /\  E. x ( x  =  y  /\  ph )
)  ->  ( (
x  =  y  ->  ps )  /\  E. x
( x  =  y  /\  ps ) ) )
6 df-sb 1761 . 2  |-  ( [ y  /  x ] ph 
<->  ( ( x  =  y  ->  ph )  /\  E. x ( x  =  y  /\  ph )
) )
7 df-sb 1761 . 2  |-  ( [ y  /  x ] ps 
<->  ( ( x  =  y  ->  ps )  /\  E. x ( x  =  y  /\  ps ) ) )
85, 6, 73imtr4i 201 1  |-  ( [ y  /  x ] ph  ->  [ y  /  x ] ps )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104   E.wex 1490   [wsb 1760
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1445  ax-gen 1447  ax-ie1 1491  ax-ie2 1492  ax-4 1508  ax-ial 1532
This theorem depends on definitions:  df-bi 117  df-sb 1761
This theorem is referenced by:  sbbii  1763  sb6f  1801  hbsb3  1806  sbidm  1849  sbco  1966  sbcocom  1968  sbalyz  1997  hbsb4t  2011  moimv  2090  elsb1  2153  elsb2  2154  oprcl  3798  peano1  4587  peano2  4588
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