Metamath Proof Explorer


Theorem exps0

Description: Surreal exponentiation to zero. (Contributed by Scott Fenton, 24-Jul-2025)

Ref Expression
Assertion exps0
|- ( A e. No -> ( A ^su 0s ) = 1s )

Proof

Step Hyp Ref Expression
1 0zs
 |-  0s e. ZZ_s
2 expsval
 |-  ( ( A e. No /\ 0s e. ZZ_s ) -> ( A ^su 0s ) = if ( 0s = 0s , 1s , if ( 0s 
3 1 2 mpan2
 |-  ( A e. No -> ( A ^su 0s ) = if ( 0s = 0s , 1s , if ( 0s 
4 eqid
 |-  0s = 0s
5 4 iftruei
 |-  if ( 0s = 0s , 1s , if ( 0s 
6 3 5 eqtrdi
 |-  ( A e. No -> ( A ^su 0s ) = 1s )