Metamath Proof Explorer


Theorem unidmovn

Description: Base set of the n-dimensional Lebesgue outer measure. (Contributed by Glauco Siliprandi, 24-Dec-2020)

Ref Expression
Hypothesis unidmovn.1
|- ( ph -> X e. Fin )
Assertion unidmovn
|- ( ph -> U. dom ( voln* ` X ) = ( RR ^m X ) )

Proof

Step Hyp Ref Expression
1 unidmovn.1
 |-  ( ph -> X e. Fin )
2 1 dmovn
 |-  ( ph -> dom ( voln* ` X ) = ~P ( RR ^m X ) )
3 2 unieqd
 |-  ( ph -> U. dom ( voln* ` X ) = U. ~P ( RR ^m X ) )
4 unipw
 |-  U. ~P ( RR ^m X ) = ( RR ^m X )
5 4 a1i
 |-  ( ph -> U. ~P ( RR ^m X ) = ( RR ^m X ) )
6 3 5 eqtrd
 |-  ( ph -> U. dom ( voln* ` X ) = ( RR ^m X ) )