Metamath Proof Explorer


Theorem s1eqd

Description: Equality theorem for a singleton word. (Contributed by Mario Carneiro, 26-Feb-2016)

Ref Expression
Hypothesis s1eqd.1 φ A = B
Assertion s1eqd φ ⟨“ A ”⟩ = ⟨“ B ”⟩

Proof

Step Hyp Ref Expression
1 s1eqd.1 φ A = B
2 s1eq A = B ⟨“ A ”⟩ = ⟨“ B ”⟩
3 1 2 syl φ ⟨“ A ”⟩ = ⟨“ B ”⟩