- Thread starter
- #1

Terms;

4, 1.4, 2.44, 2.024.... (n = 1,2,3...)

How do I find a the ratio of these terms, and if there is none, please advise how I continue?

Kind regards

Casio

- Thread starter Casio
- Start date

- Thread starter
- #1

Terms;

4, 1.4, 2.44, 2.024.... (n = 1,2,3...)

How do I find a the ratio of these terms, and if there is none, please advise how I continue?

Kind regards

Casio

- Jan 26, 2012

- 890

Could you tell us what the recurrence relation is?

Terms;

4, 1.4, 2.44, 2.024.... (n = 1,2,3...)

How do I find a the ratio of these terms, and if there is none, please advise how I continue?

Kind regards

Casio

CB

- Thread starter
- #3

UCould you tell us what the recurrence relation is?

CB

U

U

U

Four terms are;

2, 1.98, 2.11, 2.07,....

Not sure whether the first method I used to work out the terms was correct, or whether the method I used here is correct, the course book does not give any examples to show how they are done, only examples to solve?

Thanks

Casio

- Jan 26, 2012

- 890

What are you being asked to do with this sequence?U_{1}= 2, U_{n}+1 =-0.3U_{n}+ 3 (n = 1,2,3...)

U_{2}= U_{2.4+1 }= -0.3(3.4) + 3 = 1.98

U_{3 }= U_{1.98+1 }= -0.3(2.98)+3 = 2.11

U_{4 }= U_{2.11+1 }= -0.3(3.11)+3 = 2.07

Four terms are;

2, 1.98, 2.11, 2.07,....

Not sure whether the first method I used to work out the terms was correct, or whether the method I used here is correct, the course book does not give any examples to show how they are done, only examples to solve?

Thanks

Casio

It obviously has an attractor at u=30/13, increasing towards it if it starts at less than 30/13 and decreasing towards it if it starts above.

CB

You are misunderstanding the recurrence relation.

[tex]\text{Given: }\:U_{n+1} \:=\:-0.3U_n + 3,\;\;U_1 = 2[/tex]

We have:

. . . [tex]\begin{array}{cccccc}U_1 &=& 2 \\ U_2 &=& -0.3(2) + 3 &=& 2.4 \\ U_3 &=& -0.3(2.4) + 3 &=& 2.28 \\ U_4 &=& -0.3(2.28) + 3 &=& 2.316 \\ \vdots && \vdots && \vdots \end{array}[/tex]

- Thread starter
- #6

Thanks for setting me on the right line of thought there.

You are misunderstanding the recurrence relation.

[tex]\text{Given: }\:U_{n+1} \:=\:-0.3U_n + 3,\;\;U_1 = 2[/tex]

We have:

. . . [tex]\begin{array}{cccccc}U_1 &=& 2 \\ U_2 &=& -0.3(2) + 3 &=& 2.4 \\ U_3 &=& -0.3(2.4) + 3 &=& 2.28 \\ U_4 &=& -0.3(2.28) + 3 &=& 2.316 \\ \vdots && \vdots && \vdots \end{array}[/tex]

OK let me take this one step at a time so I get the proper understanding of what is actually going on with these sequences.

First, please explain what this part refers to;

[tex]\text{Given:}\:U_{n+1}[/tex]

Casio