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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 7.8.4e

4. Which of the following functions grow faster than x² as x→∞? Which grow at the same rate as x²? Which grow slower?
e. x^3 - x^2

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1
Identify the dominant term in the function \(x^3 - x^2\) as \(x \to \infty\). The dominant term is the one with the highest power of \(x\), which is \(x^3\) in this case.
Recall that the growth rate of a function as \(x \to \infty\) is determined by its highest power term. Here, \(x^3\) grows faster than \(x^2\) because the exponent 3 is greater than 2.
Compare the dominant term \(x^3\) with \(x^2\): since \(x^3\) grows faster than \(x^2\), the function \(x^3 - x^2\) grows faster than \(x^2\) as \(x \to \infty\).
To confirm, consider the limit \(\lim_{x \to \infty} \frac{x^3 - x^2}{x^2} = \lim_{x \to \infty} (x - 1) = \infty\), which shows the function grows faster than \(x^2\).
Therefore, \(x^3 - x^2\) grows faster than \(x^2\) as \(x\) approaches infinity.

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