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Ch.12 - Parametric and Polar Curves
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Non è quello che usi tu?Cambia libro di testo
Capitolo 12, Problema 12.1.31

31–36. Eliminating the parameter Eliminate the parameter to express the following parametric equations as a single equation in x and y.


x=2 sin 8t, y=2 cos 8t 

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Start with the given parametric equations: \(x = 2 \sin(8t)\) and \(y = 2 \cos(8t)\).
Isolate the trigonometric functions by dividing both \(x\) and \(y\) by 2: \(\frac{x}{2} = \sin(8t)\) and \(\frac{y}{2} = \cos(8t)\).
Recall the Pythagorean identity for sine and cosine: \(\sin^2(\theta) + \cos^2(\theta) = 1\) for any angle \(\theta\).
Substitute \(\sin(8t)\) and \(\cos(8t)\) with \(\frac{x}{2}\) and \(\frac{y}{2}\) respectively in the identity: \(\left(\frac{x}{2}\right)^2 + \left(\frac{y}{2}\right)^2 = 1\).
Simplify the equation to get a single equation in terms of \(x\) and \(y\): \(\frac{x^2}{4} + \frac{y^2}{4} = 1\).

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Parametric Equations

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