All Calculus 2 Resources
Example Questions
Example Question #7 : Geometric Series
Calculate the sum of a geometric series with the following values:
,, ,
rounded to the nearest integer.
This is a geometric series.
The sum of a geometric series can be calculated with the following formula,
, where n is the number of terms to sum up, r is the common ratio, and is the value of the first term.
For this question, we are given all of the information we need.
Solution:
Rounding,
Example Question #1 : Sequences
Calculate the sum of the following infinite geometric series:
This is an infinite geometric series.
The sum of an infinite geometric series can be calculated with the following formula,
, where is the first value of the summation, and r is the common ratio.
Solution:
Value of can be found by setting
r is the value contained in the exponent
Example Question #31 : Types Of Series
Calculate the sum of the following infinite geometric series:
This is an infinite geometric series.
The sum of an infinite geometric series can be calculated with the following formula,
, where is the first value of the summation, and r is the common ratio.
Solution:
Value of can be found by setting
r is the value contained in the exponent
Example Question #32 : Types Of Series
Calculate the sum of the following infinite geometric series:
This is an infinite geometric series.
The sum of an infinite geometric series can be calculated with the following formula,
, where is the first value of the summation, and r is the common ratio.
Solution:
Value of can be found by setting
r is the value contained in the exponent
Example Question #31 : Types Of Series
Evaluate:
The series does not converge.
The method of partial fractions can be used to rewrite this expression:
The solution can easily be found to be , and the series can then be rewritten:
The series is telescoping and is equal to the following:
Example Question #32 : Types Of Series
Evaluate:
The method of partial fractions can be used to rewrite this expression:
The solution can easily be found to be , and the series can be rewritten:
This is a telescoping series:
Example Question #1 : Harmonic Series
The Harmonic series is a special case of a -series, with equal to what?
A -series is a series of the form , and the Harmonic Series is . Hence .
Example Question #2 : Harmonic Series
Which of the following tests will help determine whether is convergent or divergent, and why?
Nth Term Test: The series diverge because the limit as goes to infinity is zero.
Root Test: Since the limit as approaches to infinity is zero, the series is convergent.
Divergence Test: Since limit of the series approaches zero, the series must converge.
Integral Test: The improper integral determines that the harmonic series diverge.
P-Series Test: The summation converges since .
Integral Test: The improper integral determines that the harmonic series diverge.
The series is a harmonic series.
The Nth term test and the Divergent test may not be used to determine whether this series converges, since this is a special case. The root test also does not apply in this scenario.
According the the P-series Test, must converge only if . Therefore this could be a valid test, but a wrong definition as the answer choice since the series diverge for .
This leaves us with the Integral Test.
Since the improper integral diverges, so does the series.
Example Question #2 : Harmonic Series
Determine whether the following series converges or diverges:
The series (absolutely) converges
The series conditionally converges
The series may (absolutely) converge, diverge, or conditionally converge
The series diverges
The series (absolutely) converges
Given just the harmonic series, we would state that the series diverges. However, we are given the alternating harmonic series. To determine whether this series will converge or diverge, we must use the Alternating Series test.
The test states that for a given series where or where for all n, if and is a decreasing sequence, then is convergent.
First, we must evaluate the limit of as n approaches infinity:
The limit equals zero because the numerator of the fraction equals zero as n approaches infinity.
Next, we must determine if is a decreasing sequence. , thus the sequence is decreasing.
Because both parts of the test passed, the series is (absolutely) convergent.
Example Question #2 : Harmonic Series
Consider the alternating series
.
Which of the following tests for convergence is NOT conclusive?
The root test
The alternating series test
The limit test for divergence
The ratio test
The limit test for divergence
Let
be the nth summand in the series. The limit test for divergence states that
implies that the series diverges.
However,
,
so the test is inconclusive.
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