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Theorem xpeq1 4637
Description: Equality theorem for cross product. (Contributed by NM, 4-Jul-1994.)
Assertion
Ref Expression
xpeq1  |-  ( A  =  B  ->  ( A  X.  C )  =  ( B  X.  C
) )

Proof of Theorem xpeq1
Dummy variables  x  y are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eleq2 2241 . . . 4  |-  ( A  =  B  ->  (
x  e.  A  <->  x  e.  B ) )
21anbi1d 465 . . 3  |-  ( A  =  B  ->  (
( x  e.  A  /\  y  e.  C
)  <->  ( x  e.  B  /\  y  e.  C ) ) )
32opabbidv 4066 . 2  |-  ( A  =  B  ->  { <. x ,  y >.  |  ( x  e.  A  /\  y  e.  C ) }  =  { <. x ,  y >.  |  ( x  e.  B  /\  y  e.  C ) } )
4 df-xp 4629 . 2  |-  ( A  X.  C )  =  { <. x ,  y
>.  |  ( x  e.  A  /\  y  e.  C ) }
5 df-xp 4629 . 2  |-  ( B  X.  C )  =  { <. x ,  y
>.  |  ( x  e.  B  /\  y  e.  C ) }
63, 4, 53eqtr4g 2235 1  |-  ( A  =  B  ->  ( A  X.  C )  =  ( B  X.  C
) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    = wceq 1353    e. wcel 2148   {copab 4060    X. cxp 4621
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 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-11 1506  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159
This theorem depends on definitions:  df-bi 117  df-tru 1356  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173  df-opab 4062  df-xp 4629
This theorem is referenced by:  xpeq12  4642  xpeq1i  4643  xpeq1d  4646  opthprc  4674  reseq2  4898  xpeq0r  5047  xpdisj1  5049  xpima1  5071  pmvalg  6653  xpsneng  6816  xpcomeng  6822  xpdom2g  6826  xpfi  6923  exmidomni  7134  exmidfodomrlemim  7194  hashxp  10790  txuni2  13423  txbas  13425  txopn  13432  txrest  13443  txdis  13444  txdis1cn  13445  xmettxlem  13676  xmettx  13677
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