Hi. I have a problem:
The length of the days of Stockholm change according to the sine function:
Where x = days, y is hours and x = 1 means January the first.
a) Determine the length of the longest and the shortest day.
b) When is day and night equally long?
I have learned that the highest value of these sine functions is 1 and the lowest is -1. I understand that, given all values for sine. However, here, the book seems to be assuming that x can take on any value and thus the highest and lowest value of the sine function is 1 and -1 in this example...But how can the book know whether the calculation inside the sine function will ever reach the values required to get the output 1 and -1 respectively?