# Cal 2 ratio test where is my mistake

1. Nov 5, 2009

### Jac8897

cal 2 ratio test "where is my mistake"

1. The problem statement, all variables and given/known data
I attached a pic
I solved the problem but i get 4^1 and the book says 4^2 I dont know why?

2. Relevant equations

http://img690.imageshack.us/img690/1518/problem15.jpg [Broken]

3. The attempt at a solution

Last edited by a moderator: May 4, 2017
2. Nov 5, 2009

### lanedance

Re: cal 2 ratio test "where is my mistake"

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

$$\frac{4^{(2n+1)}}{4^{(2(n+1)+1)}}$$

3. Nov 6, 2009

### Jac8897

Re: cal 2 ratio test "where is my mistake"

got it

thank you