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Trigonometry

Unit 2: Lesson 10

Sinusoidal models
Math
Trigonometry
Trigonometric functions
Sinusoidal models
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Modeling with sinusoidal functions: phase shift

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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
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