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Ch. 2 - Limits
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Non è quello che usi tu?Cambia libro di testo
Capitolo 2, Problema 36

Determine the following limits. 


lim x→−∞ (e^x cos x +3)

Guida verificata passo dopo passo
1
Identify the behavior of each component of the function as \( x \to -\infty \).
Recognize that \( e^x \to 0 \) as \( x \to -\infty \) because the exponential function decays to zero.
Note that \( \cos x \) oscillates between -1 and 1 for all real numbers, including as \( x \to -\infty \).
Consider the product \( e^x \cos x \). Since \( e^x \to 0 \) and \( \cos x \) is bounded, \( e^x \cos x \to 0 \) as \( x \to -\infty \).
Combine the results: \( \lim_{x \to -\infty} (e^x \cos x + 3) = 0 + 3 = 3 \).

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