Skip to main content
Ch. 10 - Sequences and Infinite Series
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Non è quello che usi tu?Cambia libro di testo
Capitolo 10, Problema 10.5.50

40–62. Choose your test Use the test of your choice to determine whether the following series converge.
∑ (k = 2 to ∞) (5lnk) / k

Guida verificata passo dopo passo
1
Identify the series given: \( \sum_{k=2}^{\infty} \frac{5 \ln k}{k} \). We want to determine if this series converges or diverges.
Since the terms involve \( \ln k \) and \( k \), consider using the Integral Test, which is suitable for series with positive, continuous, and decreasing terms for large \( k \).
Set up the corresponding integral for the Integral Test: \( \int_{2}^{\infty} \frac{5 \ln x}{x} \, dx \).
Evaluate the integral by using substitution: let \( u = \ln x \), then \( du = \frac{1}{x} dx \), so the integral becomes \( 5 \int u \, du \).
Determine whether the integral converges or diverges by evaluating the limit as the upper bound approaches infinity. If the integral converges, the series converges; if it diverges, the series diverges.

Risposta video verificata per un problema simile:

Questa soluzione video è stata consigliata dai nostri tutor come utile per risolvere questo problema.
Durata del video:
4m

Concetti chiave

Ecco i concetti essenziali che devi comprendere per rispondere correttamente alla domanda.

Convergence of Infinite Series

An infinite series converges if the sum of its terms approaches a finite limit as the number of terms grows indefinitely. Determining convergence involves analyzing the behavior of the terms and applying appropriate tests to see if the partial sums stabilize.
Video consigliato:
Percorso guidato
06:52
Convergence of an Infinite Series

Comparison and Limit Comparison Tests

These tests compare the given series to a known benchmark series. The Comparison Test checks if terms are smaller or larger than a convergent or divergent series, while the Limit Comparison Test uses the limit of the ratio of terms to determine convergence behavior.
Video consigliato:
Percorso guidato
07:45
Limit Comparison Test

Integral Test

The Integral Test relates the convergence of a series to the convergence of an improper integral of a related function. If the integral of f(x) from some point to infinity converges, then the series ∑ f(k) also converges, provided f is positive, continuous, and decreasing.
Video consigliato: