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**luca-deltodesco****Member**- Registered: 2006-05-05
- Posts: 1,470

1.

A geometric progression **U** has first term **a**, where

a) show that

,b) show that

c) hence find two possible values for the common ratio, giving youre answers in exact form

d) for the value of r for which the progression is convergenet prove that

*Last edited by luca-deltodesco (2006-06-06 07:54:17)*

The Beginning Of All Things To End.

The End Of All Things To Come.

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**Mozartmoses****Member**- Registered: 2006-04-26
- Posts: 10

By the given information, we can write the equation as........

(ar^3 - a) = 4(ar^2 - ar)

=> a(r^3 - 1) = 4ar(r - 1)

=> r^3 - 4r^2 + 4r -1 = 0

I suppose, the contant term -1 is missing in the question. Am I right?

With regards

Moses

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**luca-deltodesco****Member**- Registered: 2006-05-05
- Posts: 1,470

Mozartmoses wrote:

I suppose, the contant term -1 is missing in the question. Am I right?

ah yeh, i thought it looked a little strange, ill change in the question

The Beginning Of All Things To End.

The End Of All Things To Come.

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**luca-deltodesco****Member**- Registered: 2006-05-05
- Posts: 1,470

**2.**

given that:

prove that:

**3.**

given that:

prove that

**4.**

Given a two vector

prove that a perpendicular two vector to

*Last edited by luca-deltodesco (2006-06-06 08:01:48)*

The Beginning Of All Things To End.

The End Of All Things To Come.

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**krassi_holmz****Real Member**- Registered: 2005-12-02
- Posts: 1,908

2.

,

so:

*Last edited by krassi_holmz (2006-07-23 03:48:43)*

IPBLE: Increasing Performance By Lowering Expectations.

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