MonotonicityMedium
Question
A differentiable function f(x) is strictly increasing ∀ x ∈ R, Then -
Options
A.f′(x) > 0 ∀ x ∈ R.
B.f′(x) > 0 ∀ x ∈ R, provided it vanishes at finite number of points.
C.f′(x) > 0 ∀ x ∈ R, provided it vanishes at discrete points though the number of these discrete points may not be finite.
D.f′(x) > 0 ∀ x ∈ R, provided it vanishes at discrete points and the number of these discrete points must be infinite.