The length of daylight (in hours) in philadelphia on the tth day of the year can be modeled by the equation l(t)=12+2.8sin[2π365(t−80)]. use this model to determine how the number of hours of daylight is increasing in philadelphia on march 21. round your answer to the nearest hundredth.(assume there are 28 days in february.)

Respuesta :

There are 12 hours of daylight in Philadelphia on March 21.

There are 31 days in January, 28 days in February and 21 in March; 31+28+21=80.  Using 80 for t,

l(t) = 12+2.8sin[2π365(80-80)]
=12+2.8sin[2π365(0)]
=12+2.8sin(0)
=12+2.8(0)
=12