題目
Problem
Part I Multiple Choice
- Let be a smooth function on .
(a) If on , then must be increasing on .
(b) If on , then must be concave upward on .
(c) If , then the point must be an inflection point.
Among the above three statements, how many of them are true?
A) Only one.
B) Only two.
C) All of them.
D) None of them.