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Theorem xpeq2 4791
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 2302 . . . 4  |-  ( A  =  B  ->  (
y  e.  A  <->  y  e.  B ) )
21anbi2d 468 . . 3  |-  ( A  =  B  ->  (
( x  e.  C  /\  y  e.  A
)  <->  ( x  e.  C  /\  y  e.  B ) ) )
32opabbidv 4198 . 2  |-  ( A  =  B  ->  { <. x ,  y >.  |  ( x  e.  C  /\  y  e.  A ) }  =  { <. x ,  y >.  |  ( x  e.  C  /\  y  e.  B ) } )
4 df-xp 4782 . 2  |-  ( C  X.  A )  =  { <. x ,  y
>.  |  ( x  e.  C  /\  y  e.  A ) }
5 df-xp 4782 . 2  |-  ( C  X.  B )  =  { <. x ,  y
>.  |  ( x  e.  C  /\  y  e.  B ) }
63, 4, 53eqtr4g 2296 1  |-  ( A  =  B  ->  ( C  X.  A )  =  ( C  X.  B
) )
Colors of variables:    wff set class
This proof depends on syntax axioms:    -> wi 4    /\ wa 104    = wceq 1402    e. wcel 2209   {copab 4192    X. cxp 4774
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-11 1559  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220
This proof depends on definitions:  df-bi 117  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-opab 4194  df-xp 4782
This theorem is used by:  xpeq12  4795  xpeq2i  4797  xpeq2d  4800  xpeq0r  5213  xpdisj2  5216  pmvalg  6937  xpcomeng  7130  djueq12  7385  gsum2d2fi  14274  txuni2  15482  txbas  15484  txopn  15491  txrest  15502  txdis  15503  txdis1cn  15504  xmettxlem  15735  xmettx  15736
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