All Calculus 2 Resources
Example Questions
Example Question #176 : Series In Calculus
If and , and it may be said that converges, what may be said about ?
Converges by the comparison test.
Converges by the ratio test.
Diverges by the comparison test.
Converges by the test for convergence of geometric series.
Diverges by the ratio test.
Converges by the comparison test.
Given two series,
and
where
converges,
the Comparison Test states that the second series
must also converge, if and only if, it is smaller than the first.
Example Question #1 : Types Of Series
Evaluate:
The series diverges.
This can be rewritten as
, so , making this a convergent geometric series with initial term and common ratio . The sum is therefore
.
Example Question #2 : Types Of Series
Evaluate:
The series diverges.
This can be rewritten as
.
This is a geometric series with initial term and common ratio . Since , , and the series converges to:
Example Question #1 : Types Of Series
Evaluate:
The series is not convergent.
is an infinite geometric series with initial term and common ratio . The sum is therefore
Example Question #1 : Types Of Series
Evaluate:
is a geometric series with initial term and common ratio . The sum of this series is
.
Example Question #1 : Types Of Series
How many terms of a geometric series must you know in order to uniquely define that series?
Three
One
Four
Five
Two
Two
In order to uniquely define the geometric series, we need to know two things: the ratio between successive terms and at least one of the terms. Knowing one term doesn't give you the ratio of successive terms, but knowing two terms will give you the ratio. By the term generator for a geometric series , you can see that you only need two terms to find the ratio .
Example Question #1 : Arithmetic And Geometric Series
Assume the term generator for an arithmetic sequence is . What is the sum of the first terms of this sequence ?
The sum formula for terms of an arithmetic series is .
For terms, this formula becomes .
Using our term generator for and , this formula becomes
.
Example Question #1 : Arithmetic And Geometric Series
What value does the series approach?
We can evaluate the infinite series by recognizing it as a geometric series times some constant.
Let's manipulate this series:
.
Now it suffices to evaluate , which we can recognize as the power series of with , which is
.
So we have
.
Example Question #181 : Series In Calculus
Determine whether the series is arithmetic. If so, find the common difference.
Series is not arithmetic
Series is not arithmetic
If a series is arithmetic, then there exists a common difference between each pair of consecutive terms in the series.
For this series
Because
and
we find that there does NOT exist a common difference and as such,
the series is not arithmetic.
Example Question #3 : Arithmetic And Geometric Series
Determine whether or not the geometric series converges. If it converges, find the sum of the sequence.
Series does not converge.
Series does not converge.
To determine the convergency of a geometric series, we must find the absolute value of the common ratio.
A geometric series will converge if the absolute value of the common ratio is less than one, or
In this problem, we see that
And because
we conclude that the series does not converge to a finite sum.
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