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Metamath Proof Explorer

Theorem deceq2

Description: Equality theorem for the decimal constructor. (Contributed by Mario Carneiro, 17-Apr-2015) (Revised by AV, 6-Sep-2021)

Ref Expression
Assertion deceq2 Could not format assertion : No typesetting found for |- ( A = B -> ; C A = ; C B ) with typecode |-

Proof

Step Hyp Ref Expression
1 oveq2 ⊢ A = B → 9 + 1 ⁢ C + A = 9 + 1 ⁢ C + B
2 df-dec Could not format ; C A = ( ( ( 9 + 1 ) x. C ) + A ) : No typesetting found for |- ; C A = ( ( ( 9 + 1 ) x. C ) + A ) with typecode |-
3 df-dec Could not format ; C B = ( ( ( 9 + 1 ) x. C ) + B ) : No typesetting found for |- ; C B = ( ( ( 9 + 1 ) x. C ) + B ) with typecode |-
4 1 2 3 3eqtr4g Could not format ( A = B -> ; C A = ; C B ) : No typesetting found for |- ( A = B -> ; C A = ; C B ) with typecode |-