The pressure P in lbsft2 in a pipe varies over time 6 times

The pressure, P (in lbs/ft²), in a pipe varies over time. 6 times an hour, the pressure oscillates from a low of 106 to a high of 250 and then back to a low 106. The pressure at t=0 is 106.

Find a possible formula for P=f(t), where t is time in minutes. Assume there is no phase shift.

f(t)=

Solution

f(t) = (72 lb/ft^2)*cos(12*pi*t) + (59.33 lb/ft^2)
where \"t\" is measured in hours.