Theorem frege54cor1b 43856

Description: Reflexive equality. (Contributed by RP, 24-Dec-2019.)

Assertion

Ref	Expression
frege54cor1b	⊢ [𝑥 / 𝑦]𝑦 = 𝑥

Proof of Theorem frege54cor1b

Step	Hyp	Ref	Expression
1		equsb1 2499	1 ⊢ [𝑥 / 𝑦]𝑦 = 𝑥

Syntax hints:  [wsb 2064

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1793  ax-4 1807  ax-5 1909  ax-6 1967  ax-7 2007  ax-10 2141  ax-12 2178  ax-13 2380

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 847  df-ex 1778  df-nf 1782  df-sb 2065

This theorem is referenced by:  frege55lem2b  43858