A variable star is one whose brightness alternately increases and decreases. For the most visible variable star, Delta Cephei, the time between periods of maximum brightness is 5.4 days, the average brightness (or magnitude) of the star is 4.0, and its brightness varies by $ \pm 0.35 $ magnitude. Find
a function that models the brightness of Delta Cephei as a function of time.
Hey, it's clear. So when you read here, so we have the period of time between maximum brightness of the star is 5.4 days. So we get five point for a sequel to two pi over B, and we gotta be value uh, pi over 2.7. You have an average value of four soc. It's equal to four, and we have magnitude from the average value is plus or minus 0.35 So we get the amplitude to be 0.35 when we put this all together and our equation is 0.35 sign, uh, pie over 2.70 plus four.