Question

The function f(t) = 4 cos(pi over 3t) + 15 represents the tide in Bright Sea. It has a maximum of 19 feet when time (t) is 0 and a minimum of 11 feet. The sea repeats this cycle every 6 hours. After five hours, how high is the tide?
13.5 feet

16 feet

18.5 feet

17 feet

@SolomonZelman @YanaSidlinskiy

Answer 1

@Gin_Ichimaru @amistre64 @VortexAlliby @KlOwNlOvE

Answer 2

what is cos(5pi/3)?

Answer 3

you need to find the hight of the tide after 5 hours so do cos(5pi/3)

Answer 4

cos (5pi/3) is 1/2 @KlOwNlOvE

Answer 5

now do 4*.5+15

Answer 6

http://openstudy.com/study#/updates/539cb3b0e4b0eb8de56da0b0
If you want a better explination

Answer 7

17?

Answer 8

yes