Let N=1,2,3,.... For real x,y, set S(x,y)={s∣s=[nx+y],n∈N}. Prove that if r>1 is a rational number, there exist real numbers u and v such that
S(r,0)∩S(u,v)=∅,S(r,0)∪S(u,v)=N. floor functioninequalitiesnumber theoryrelatively primenumber theory proposed