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Ch. 7 - Transcendental Functions
Hass - Thomas' Calculus 15th Edition
Hass15th EditionThomas' CalculusISBN: 9780137616077Non è quello che usi tu?Cambia libro di testo
Capitolo 7, Problema 7.5.12

Use l’Hôpital’s rule to find the limits in Exercises 7–52.


12. lim (x → ∞) (x - 8x²) / (12x² + 5x)

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1
Identify the limit expression: \(\lim_{x \to \infty} \frac{x - 8x^{2}}{12x^{2} + 5x}\).
Check the form of the limit by analyzing the degrees of the numerator and denominator as \(x\) approaches infinity. Both numerator and denominator tend to infinity, so the limit is of the form \(\frac{\infty}{\infty}\), which is an indeterminate form suitable for l'Hôpital's Rule.
Apply l'Hôpital's Rule by differentiating the numerator and denominator separately with respect to \(x\): differentiate numerator \(\frac{d}{dx}(x - 8x^{2})\) and denominator \(\frac{d}{dx}(12x^{2} + 5x)\).
Write the new limit expression using the derivatives: \(\lim_{x \to \infty} \frac{\frac{d}{dx}(x - 8x^{2})}{\frac{d}{dx}(12x^{2} + 5x)}\).
Evaluate the new limit by simplifying the derivatives and then analyzing the behavior as \(x\) approaches infinity to find the limit.

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