A set X⊂R has dimension zero if, for any ϵ>0 there exists a positive integer k and intervals I1,I2,...,Ik such that X⊂I1∪I2∪⋯∪Ik with ∑j=1k∣Ij∣ϵ<ϵ.Prove that there exist sets X,Y⊂[0,1] both of dimension zero, such that X+Y=[0,2]. CIIMCIIM 2010undergraduate