Metamath Proof Explorer


Theorem dfdec10

Description: Version of the definition of the "decimal constructor" using ; 1 0 instead of the symbol 10. Of course, this statement cannot be used as definition, because it uses the "decimal constructor". (Contributed by AV, 1-Aug-2021)

Ref Expression
Assertion dfdec10 Could not format assertion : No typesetting found for |- ; A B = ( ( ; 1 0 x. A ) + B ) with typecode |-

Proof

Step Hyp Ref Expression
1 df-dec Could not format ; A B = ( ( ( 9 + 1 ) x. A ) + B ) : No typesetting found for |- ; A B = ( ( ( 9 + 1 ) x. A ) + B ) with typecode |-
2 9p1e10 9 + 1 = 10
3 2 oveq1i 9 + 1 A = 10 A
4 3 oveq1i 9 + 1 A + B = 10 A + B
5 1 4 eqtri Could not format ; A B = ( ( ; 1 0 x. A ) + B ) : No typesetting found for |- ; A B = ( ( ; 1 0 x. A ) + B ) with typecode |-