15-05-2005, 13:12
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#1
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Guest
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Maths help needed!
Hey, doing some revision here and I just can't for the life of me work out how do this:
I needed to factorise this term by x:
xlog(a)
________ = 1
xlog(2b)
How do you factorise a fraction by a term which is on top and bottom?
Help would be appreciated, thanks
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15-05-2005, 13:25
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#2
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Eva Longoria Fan
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Re: Maths help needed!
Im sure you divide it
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15-05-2005, 13:27
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#3
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Ghost Process Killer
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Re: Maths help needed!
I would have said it doesnt factorise, since if you divide both top and bottom by x then x disappears from the equation altogther, leaving : log(a) / log(2b) = 1
thus log(a) = log(2b)from which a=2b
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15-05-2005, 13:56
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#4
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Guest
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Re: Maths help needed!
Quote:
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Originally Posted by MetaWraith
I would have said it doesnt factorise, since if you divide both top and bottom by x then x disappears from the equation altogther, leaving : log(a) / log(2b) = 1
thus log(a) = log(2b)from which a=2b
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Yeah that's what I thought but unfortunately I was told find x?
I think the question is wrong.
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15-05-2005, 14:20
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#5
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cf.ChavyType
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Re: Maths help needed!
It is. However you look at it x cancels.
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15-05-2005, 14:22
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#6
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Re: Maths help needed!
So x=0 ?
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15-05-2005, 14:39
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#7
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Permanently Banned
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Re: Maths help needed!
Quote:
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Originally Posted by Zeph
So x=0 ? 
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Nope, x can be any number but 0 provided that a=2b.
Are you sure you typed the equation correctly?
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15-05-2005, 14:41
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#8
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Dr Pepper Addict
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Re: Maths help needed!
x is anything you like, except 0 (you can't divide by zero).
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15-05-2005, 15:19
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#9
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Guest
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Re: Maths help needed!
Thanks everyone
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15-05-2005, 17:07
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#10
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Inactive
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Re: Maths help needed!
Quote:
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Originally Posted by Paul M
x is anything you like, except 0 (you can't divide by zero).
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it doesn't make sense to you computing folk, but i spent a good while in pure maths classes trying to figure out what 0/0 is in various cases... 
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if you rearrange such that log(a^x)=log((2b)^x), then theres no reason x cant be zero
apologies for pedantry!
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15-05-2005, 18:02
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#11
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cf.ChavyType
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Re: Maths help needed!
Quote:
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Originally Posted by bmxbandit
if you rearrange such that log(a^x)=log((2b)^x), then theres no reason x cant be zero
apologies for pedantry!
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Surely there is- as it's still re-arrangeable back to x log a = x log y, and that cancels. It's also still common to both sides as it is there as well.
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15-05-2005, 18:22
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#12
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Inactive
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Re: Maths help needed!
Quote:
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Originally Posted by nffc
Surely there is- as it's still re-arrangeable back to x log a = x log y, and that cancels. It's also still common to both sides as it is there as well.
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...but the possiblity of it being zero is still there, you only 'cancel' to discard the trivial answer!
anyway, far too deep in. i'll shut up now
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15-05-2005, 23:37
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#13
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Re: Maths help needed!
I've a similar problem (Is this off topic?)
£1 = 100 p
= (10p) * (10p)
= (£0.1) * (£0.1)
= £0.01
= 1p
So, £1 = 1 penny. What the!
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15-05-2005, 23:42
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#14
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cf.addict
Join Date: Jul 2004
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Re: Maths help needed!
Quote:
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Originally Posted by Orior
= (10p) * (10p)
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eh no
= 10p * 10
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16-05-2005, 00:55
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#15
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cf.ChavyType
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Re: Maths help needed!
Quote:
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Originally Posted by Paddy1
Quote:
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Originally Posted by Orior
= (10p) * (10p)
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eh no
= 10p * 10
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Exactly what I was going to say... you can't factorise as well as take the units to two quantities in the process.
Going from £1 = 100p to 10*10p is fine but multiplying 10p*10p gives 10p^2.
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