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Ch. 1 - Angles and the Trigonometric Functions
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601Non è quello che usi tu?Cambia libro di testo
Capitolo 1, Problema 39

In Exercises 33–42, let sin t = a, cos t = b, and tan t = c. Write each expression in terms of a, b, and c.
sin(-t - 2𝜋) - cos(-t - 4𝜋) - tan(-t - 𝜋)

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Recall the even-odd properties of trigonometric functions: \(\sin(-x) = -\sin x\), \(\cos(-x) = \cos x\), and \(\tan(-x) = -\tan x\).
Use the periodicity of the functions: \(\sin(x - 2\pi) = \sin x\), \(\cos(x - 4\pi) = \cos x\), and \(\tan(x - \pi) = \tan x\).
Apply these properties to each term in the expression: - For \(\sin(-t - 2\pi)\), rewrite as \(\sin(-(t + 2\pi)) = -\sin(t + 2\pi) = -\sin t = -a\). - For \(\cos(-t - 4\pi)\), rewrite as \(\cos(-(t + 4\pi)) = \cos(t + 4\pi) = \cos t = b\). - For \(\tan(-t - \pi)\), rewrite as \(\tan(-(t + \pi)) = -\tan(t + \pi) = -\tan t = -c\).
Substitute the simplified terms back into the original expression: \(\sin(-t - 2\pi) - \cos(-t - 4\pi) - \tan(-t - \pi) = (-a) - b - (-c)\).
Simplify the expression by combining like terms: \(-a - b + c\).

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