Question 65
a. Prove that the unit square can be covered by three sets of diameter not exceeding $\frac{\sqrt{65}}{8}$.
b. Prove that the unit square can not be covered by three sets of diameter less than $\frac{\sqrt{65}}{8}$.
b. Prove that the unit square can not be covered by three sets of diameter less than $\frac{\sqrt{65}}{8}$.