C D wwwwebassign Responsessubmitdep 16041606 netwebStudentAs

C D www.webassign. Responsessubmit?dep 16041606 net/web/Student/Assignment 9. 14 points l Previous Answers SAlgTrig4 6.3.086. Variable stars are ones whose brightness varies periodically. The brightness of a certain star is modeled by the function b(t) 8.9 2.8 159 where t is measured in days. (a) Find the period. days (b) Find the maximum and minimum brightness. (minimum) (maximum) (c) Graph the function b. 8,9 318 318 INMa 5418 Turki Alme... lpg

Solution

Period=2pi/B=2pi/pi/159=318

Maximum brightness is when cos (pit/159)=-1

b(t)=8.9-2.8(-1)=8.9+2.8=11.7

Minimum is when cos (pi t/159)=1

b(t)=8.9-2.8=6.1