# Math Help - Vitali set

1. ## Vitali set

I need help with this problem, i couldn't find a proof in any book related to measure theory.
Show that every Lebesgue measurable subset of a Vitali set V is a Lebesgue nullset.

2. Translates of the Vitali set are disjoint from it.
Suppose it had a measurable subset of nonzero measure. By translating this subset by all rationals in the unit interval, you obtain a countable collection of disjoint sets of real numbers in the interval [0,2], who all have the same nonzero measure (by translation invariance of measure); their countable union is measurable, and since it's a subset of [0,2], it must have finite measure. See what you can make of all this.

3. Thanks, i did not know these facts from before..