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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 2.59

Evaluate limx→∞f(x){\(\displaystyle\[\lim\)_{x\(\to\]\infty\)}{f(x)}} andlimx→−∞f(x){\(\displaystyle\)\(\lim\)_{x\(\to\)-\(\infty\)}{f(x)}}.


f(x)=6ex+203ex+4f\(\left\)(x\(\right\))=\(\frac{6e^{x}\)+20}{3e^{x}+4}

Guida verificata passo dopo passo
1
Identify the function for which you need to find the limits: \( f(x) = \frac{6e^{x} + 20}{3e^{x} + 4} \).
To evaluate \( \lim_{x \to \infty} f(x) \), divide the numerator and the denominator by \( e^x \), the highest power of \( e \) in the expression. This simplifies the function to \( \frac{6 + \frac{20}{e^x}}{3 + \frac{4}{e^x}} \).
As \( x \to \infty \), the terms \( \frac{20}{e^x} \) and \( \frac{4}{e^x} \) approach 0 because \( e^x \) grows exponentially. Thus, the expression simplifies to \( \frac{6}{3} \).
Now, evaluate \( \lim_{x \to -\infty} f(x) \). In this case, \( e^x \to 0 \) as \( x \to -\infty \), so the function simplifies to \( \frac{20}{4} \).
Conclude by stating the limits: \( \lim_{x \to \infty} f(x) = 2 \) and \( \lim_{x \to -\infty} f(x) = 5 \).

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