could you explain what is being done in this example.
y=-0.37cos pi/2t+0.45
y=0.37cos[pi/2(5.5)]+0.45
y=0.711629509
looks like t was replaced by 5.5
then in the evaluation an error was made
I got .18837, with my calculator set to radians.
(even with degrees, the answer given is wrong)