Metamath Proof Explorer


Theorem dmovnsal

Description: The domain of the Lebesgue measure is a sigma-algebra. (Contributed by Glauco Siliprandi, 24-Dec-2020)

Ref Expression
Hypotheses dmovnsal.x
|- ( ph -> X e. Fin )
dmovnsal.s
|- S = dom ( voln ` X )
Assertion dmovnsal
|- ( ph -> S e. SAlg )

Proof

Step Hyp Ref Expression
1 dmovnsal.x
 |-  ( ph -> X e. Fin )
2 dmovnsal.s
 |-  S = dom ( voln ` X )
3 1 vonmea
 |-  ( ph -> ( voln ` X ) e. Meas )
4 3 2 dmmeasal
 |-  ( ph -> S e. SAlg )