(- n ) n (-

Algebra & Trigonometry with Analytic Geometry
13th Edition
ISBN:9781133382119
Author:Swokowski
Publisher:Swokowski
Chapter3: Functions And Graphs
Section3.4: Definition Of Function
Problem 48E
icon
Related questions
Question
100%

can you please answer both questions. Decide whether those two series will converge. Thank you

(-
n
)
n
(-
Transcribed Image Text:(- n ) n (-
Expert Solution
Step 1

Given series

(-1)" logn
n 1
To prove: If the given series converges
Step 2

Note: We use the Ratio test which is given as

an+1
L lim
n co an
If L<1, then the series converges
If L 1, then the series diverges.
If L 1 or the limit fails to exist, then the test is inconclusive.
Step 3

Applying the rule,

(-1)n+1 log(n1)
n+1
(-1)n log n
an+1
lim
n-o an
lim
n co
(-1)"+1 log(n1)
lim
(-1) log n
n1
noo
(-1)" (1) log(n + 1)
lim
n
n 1
(-1) log(n 1)
n 1
(-1)" log n
nco
n
lim
logn
n 0o
log(n1)
- lim
n 1
log n
n-co
log(n1)
=-lim
n co
n 1
logn
log(n 1)
lim
=-lim
n 1
n-00 logn
noo
Step 4

We solve it individually.

On applying the limit, we get the indeterminant form, thus we use the
L'Hospital Rule i.e. differentiate the numerator and differentiate the
denominator and then take the limit.
1
1
n1
= -lim
*lim
1/n
1
n o0
n-oo
= 0
Hence, the series converges
steps

Step by step

Solved in 7 steps with 7 images

Blurred answer
Knowledge Booster
Series
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, calculus and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Algebra & Trigonometry with Analytic Geometry
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:
9781133382119
Author:
Swokowski
Publisher:
Cengage