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	$$⊢A=B\to \left(9+1\right)C+A=\left(9+1\right)C+B$$
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 |-