Theorem frege54cor1b 44697

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 2525	1 ⊢ [𝑥 / 𝑦]𝑦 = 𝑥

This proof depends on syntax axioms:  [wsb 2099

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-10 2179  ax-12 2216  ax-13 2406

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-ex 1813  df-nf 1817  df-sb 2100

This theorem is used by:  frege55lem2b  44699