If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.

Main content

Modeling with sinusoidal functions: phase shift

Problem

The length of the day in Lagos, Nigeria (in minutes), t days since the beginning of the year can be estimated by this formula:
L, left parenthesis, t, right parenthesis, equals, 727, plus, 22, sine, left parenthesis, start fraction, 2, pi, left parenthesis, t, minus, 80, point, 75, right parenthesis, divided by, 365, end fraction, right parenthesis.
When is the longest day of the year? Give an exact answer.
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0, point, 75
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
days since the beginning of the year
Stuck?
Stuck?