Maxima and minima

How many extreme values does sin4x + 2x, where 0 < x < π/2 have?

The function y has a relative maxima at x = 0 for

Direction: Consider the following for the next two items
that follow:

What is the greatest value of f(x)?

What is the least value of f(x)?

Direction for Questions (63-64): Consider the following for the two (02) items that follow: Let the function f(x) = x² + 9.

 Consider the following statements:

 I. f(x) is an increasing function.

II. f(x) has local maximum at x = 0

 Which of the statements given above is/are correct?