Cal 2 ratio test where is my mistake

In summary, the Cal 2 ratio test is a method used in calculus to determine the convergence or divergence of an infinite series by comparing the ratio of consecutive terms to a limit. To perform the test, you need to take the limit of the ratio as n approaches infinity. The purpose of the test is to determine convergence for certain series that the comparison test cannot. Common mistakes occur when taking the limit of the ratio, so it is important to simplify and check your work. The test can only be used for series with positive terms and cannot be used for series with alternating signs.
  • #1
Jac8897
25
0
cal 2 ratio test "where is my mistake"

Homework Statement


I attached a pic
I solved the problem but i get 4^1 and the book says 4^2 I don't know why?

Homework Equations



http://img690.imageshack.us/img690/1518/problem15.jpg

The Attempt at a Solution

 
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  • #2


when you sub in for n -> n+1 in exponent of the 4 it should be

[tex] \frac{4^{(2n+1)}}{4^{(2(n+1)+1)}}[/tex]
 
  • #3


lanedance said:
when you sub in for n -> n+1 in exponent of the 4 it should be

[tex] \frac{4^{(2n+1)}}{4^{(2(n+1)+1)}}[/tex]

got it

thank you
 

Related to Cal 2 ratio test where is my mistake

1. What is the Cal 2 ratio test?

The Cal 2 ratio test is a method used in calculus to determine the convergence or divergence of an infinite series. It involves comparing the ratio of consecutive terms in the series to a limit, and if that limit is less than 1, the series is said to converge.

2. How do I perform the Cal 2 ratio test?

To perform the Cal 2 ratio test, you need to first take the limit of the ratio of consecutive terms in the series as n approaches infinity. If this limit is less than 1, then the series converges. If the limit is greater than 1 or does not exist, then the series diverges.

3. What is the purpose of the Cal 2 ratio test?

The Cal 2 ratio test is used to determine the convergence or divergence of infinite series. It is a more powerful test than the basic comparison test, as it can determine convergence for certain series that the comparison test cannot.

4. Where do mistakes commonly occur when using the Cal 2 ratio test?

Mistakes commonly occur when taking the limit of the ratio of consecutive terms, as this can involve complicated algebraic manipulations. It is important to carefully simplify and check your work to avoid errors.

5. Can the Cal 2 ratio test be used for all infinite series?

No, the Cal 2 ratio test can only be used for series with positive terms. It also cannot be used for series with alternating signs, such as the alternating harmonic series. In these cases, other tests such as the alternating series test must be used.

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