Proving the Existence of an Interval in a Lebesgue Measure Space

Funky1981
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Homework Statement


Let (R,M,m) be Lebesgue measure space in R. Given E contained in R with m(E)>0 show that the set
E-E defined by

E-E:={x in R s.t. exists a, b in E with x= a-b }

contains an interval centered at the origin

Homework Equations



try to prove by contradiction and use the fact that for every a in (0,1) there exists an interval I s.t. m(E∩ I)>am(I)
 
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