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#1 2006-06-05 02:28:33
- luca-deltodesco
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Luca's Puzzles (math)
1.
A geometric progression U has first term a, where
a) show that ,
b) show that (r-1) is a factor of . hence factorise.
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 (2006-06-07 05:54:17)
The Beginning Of All Things To End.
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#2 2006-06-05 07:45:50
- Mozartmoses
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Re: Luca's Puzzles (math)
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
#3 2006-06-06 01:06:06
- luca-deltodesco
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Re: Luca's Puzzles (math)
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.
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#4 2006-06-07 04:45:34
- luca-deltodesco
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Re: Luca's Puzzles (math)
2.
given that:
prove that:
3.
given that:
prove that
4.
Given a two vector
prove that a perpendicular two vector to a is:
Last edited by luca-deltodesco (2006-06-07 06:01:48)
The Beginning Of All Things To End.
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#5 2006-07-24 01:44:01
- krassi_holmz
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Re: Luca's Puzzles (math)
2.
,
so:
Last edited by krassi_holmz (2006-07-24 01:48:43)
IPBLE: Increasing Performance By Lowering Expectations.