Find the intervals on which f is increasing and decreasing

f(x) = 3cos(3x) on [-pi, pi]

What are the relative frequencies, to the nearest hundredth, of the rows of the two-way table? group 1: a 15 b 45 group 2: a 20 b 25

What is the average diastolic blood pressure for adults

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years