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Theorem xpeq2 4428
Description: Equality theorem for cross product. (Contributed by NM, 5-Jul-1994.)
Assertion
Ref Expression
xpeq2  |-  ( A  =  B  ->  ( C  X.  A )  =  ( C  X.  B
) )

Proof of Theorem xpeq2
Dummy variables  x  y are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eleq2 2148 . . . 4  |-  ( A  =  B  ->  (
y  e.  A  <->  y  e.  B ) )
21anbi2d 452 . . 3  |-  ( A  =  B  ->  (
( x  e.  C  /\  y  e.  A
)  <->  ( x  e.  C  /\  y  e.  B ) ) )
32opabbidv 3881 . 2  |-  ( A  =  B  ->  { <. x ,  y >.  |  ( x  e.  C  /\  y  e.  A ) }  =  { <. x ,  y >.  |  ( x  e.  C  /\  y  e.  B ) } )
4 df-xp 4419 . 2  |-  ( C  X.  A )  =  { <. x ,  y
>.  |  ( x  e.  C  /\  y  e.  A ) }
5 df-xp 4419 . 2  |-  ( C  X.  B )  =  { <. x ,  y
>.  |  ( x  e.  C  /\  y  e.  B ) }
63, 4, 53eqtr4g 2142 1  |-  ( A  =  B  ->  ( C  X.  A )  =  ( C  X.  B
) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 102    = wceq 1287    e. wcel 1436   {copab 3875    X. cxp 4411
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-5 1379  ax-7 1380  ax-gen 1381  ax-ie1 1425  ax-ie2 1426  ax-8 1438  ax-11 1440  ax-4 1443  ax-17 1462  ax-i9 1466  ax-ial 1470  ax-i5r 1471  ax-ext 2067
This theorem depends on definitions:  df-bi 115  df-tru 1290  df-nf 1393  df-sb 1690  df-clab 2072  df-cleq 2078  df-clel 2081  df-opab 3877  df-xp 4419
This theorem is referenced by:  xpeq12  4432  xpeq2i  4434  xpeq2d  4437  xpeq0r  4822  xpdisj2  4824  pmvalg  6370  xpcomeng  6498  djueq12  6679
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