Let U=[-1,-0.3]\cup [0.3,1]. Let W(x):=1 and D(x)={(0, if x in [-1,-0.3],),(1, if x in [0.3,1].):}
Consider the following polynomial approximation of D(*) over U. How many alternation points it has?
Comment: Don't use a microscopic vision. Wherever the polynomial is almost touching dotted lines, it is indeed
touching it.
Answer:
The correct answer is: 7