Let S be the set of all non-zero real numbers α such that the quadratic equation αx2−x+α=0 has two distinct real roots x1 and x2 satisfying ∣x1−x2∣<1. Which of the following intervals are subsets of S?
(1) (−21,−51)
(2) (−51,0)
(3) (0,51)
(4) (51,21)