The temperature of a liquid during an experiment can be modeled by the function f(x)=3.8cos(πx20)+2.2 , where f(x) is the temperature in °C and x is the number of minutes into the experiment.
What is the lowest temperature the liquid reached during the experiment?
Round to the nearest tenth of a degree if needed.
Use 3.14 for π .
I think it is -1.6
The amplitude of the cos wave will be 3.8 and it will be shifted UP 2.2
Max will be 3.8 + 2.2 = 6 C
Min will be -3.8 + 2.2 = -1.6 C as you found!
Note: this assumes the expiriment runs through at least ONE half period of the wave starting at t=0 !
( Period of wave = 2pi/(20pi) = 1/10 of a minute=6 seconds..... 1/2 period = 3 seconds)