2m (x) y (x) = Ev(x). I want you to see is that v(x) and v'(x) should be continuous functions if the po y V (x) is everywhere finite. rounded kink I XO (a) (b) Figure 1: (a) A wave function v(x) with a kink. (b) The kink now rounded. ) We'll start with '(x). Fig. la shows an example of a wave function v(x) that