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Theorem csbeq1a 3145
Description: Equality theorem for proper substitution into a class. (Contributed by NM, 10-Nov-2005.)
Assertion
Ref Expression
csbeq1a (x = AB = [A / x]B)

Proof of Theorem csbeq1a
StepHypRef Expression
1 csbid 3144 . 2 [x / x]B = B
2 csbeq1 3140 . 2 (x = A[x / x]B = [A / x]B)
31, 2syl5eqr 2399 1 (x = AB = [A / x]B)
Colors of variables: wff setvar class
Syntax hints:  wi 4   = wceq 1642  [csb 3137
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334
This theorem depends on definitions:  df-bi 177  df-an 360  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-sbc 3048  df-csb 3138
This theorem is referenced by:  csbhypf  3172  csbiebt  3173  sbcnestgf  3184  cbvralcsf  3199  cbvreucsf  3201  cbvrabcsf  3202  csbing  3463  csbifg  3691  sbcbrg  4686  opeliunxp  4821  csbima12g  4956  csbovg  5553  fvmpts  5702  fvmpt2i  5704  fvmptex  5722  fmpt2x  5731
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