calculus (gr 12)
posted by Maria .
the productivity of a person at work (on a scale of 010) is modeled by a cosine function: 5cos (pie/2t) +5, where t is in hours. If the person starts work at t=0, being 8:00 am, at what times is the worker the least productive?
a) 12pm
B) 10 am and 2pm
C) 11 am and 3 pm
D) 10 am,12pm and 2 pm
MULTIPLE CHOICE

calculus (gr 12) 
Steve
cos has max at t=0
cos(pi/2 t) has period 4
cos has min at 1/2 the period.
so,
f(0) (8am) = 5*1+5 = 10
f(1) (9am) = 5*0+5 = 5
f(2) (10am) = 5*(1) + 5 = 0
...
least productive at 10:00,14:00,...
(B)
Respond to this Question
Similar Questions

Business Law
Which of the following is true about determining whether someone working for another is an independent contractor or an employee? 
Physics
A rescue helicopter lifts a 65 kg person straight up by means of a cable. The person has an upward acceleration of 0.70 m/s2 and is lifted from rest through a distance of 13 m. (a) What is the tension in the cable? 
Physics
A rescue helicopter lifts a 65 kg person straight up by means of a cable. The person has an upward acceleration of 0.70 m/s2 and is lifted from rest through a distance of 13 m. (a) What is the tension in the cable? 
Math/Management
Ten jobs are to be completed by three workers (Sam, Joy, and Kelly) during the next week. Each person works a 40hour week and is paid an hourly rate: Sam, Joy, and Kelly earn $11, $13, and $14 per hour, respectively. Union rules require … 
Quick Math Question
How do I add time? If a person worked 4 1/2 hours on Monday, 4 1/2 hours on Tuesday and 2 hours on Wednesday, does that add up to 12 hours? 
math 12
the productivity of a person at work (on a scale of 010) is modeled by a cosine function: 5cos (pie/2t) +5, where t is in hours. If the person starts work at t=0, being 8:00 am, at what times is the worker the least productive? 
CALC
the productivity of a person at work (on a scale of 010) is modeled by a cosine function: 5cos (pie/2t) +5, where t is in hours. If the person starts work at t=0, being 8:00 am, at what times is the worker the least productive? 
Math
One person can complete a piece of work in 8 days while other person can complete the same work in 4 days(if both works 10 hours per day). how many hours are required to complete the same work if both persons do it combined? 
Calc
the productivity of a person at work is modeled by a cosine function: 5cos (pie/2 (t)) +5, where t is in hours. If the person starts work at t=0, being 8:00 am, at what times is the worker the least productive? 
math
the productivity of a person is modelled by the function y=5cos(pi/2 t)+5, where t is in hours and t>and equal to 0. if the person starts work at 8:00am and works for 12 hours determine at what times they are least productive.assume …