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Ch. 3 - Trigonometric Identities and Equations
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601Non è quello che usi tu?Cambia libro di testo
Capitolo 3, Problema 102

In Exercises 97–116, use the most appropriate method to solve each equation on the interval [0, 2𝝅). Use exact values where possible or give approximate solutions correct to four decimal places. cos x - 5 = 3 cos x + 6

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Start by writing down the given equation: \(\cos x - 5 = 3 \cos x + 6\).
Group like terms to isolate the cosine terms on one side. Subtract \(\cos x\) from both sides and subtract 6 from both sides to get: \(-5 - 6 = 3 \cos x - \cos x\).
Simplify both sides: \(-11 = 2 \cos x\).
Solve for \(\cos x\) by dividing both sides by 2: \(\cos x = \frac{-11}{2}\).
Analyze the value of \(\cos x = -\frac{11}{2}\). Since cosine values must be between -1 and 1, this equation has no solution on the interval \([0, 2\pi)\).

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