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#1 2008-03-03 07:43:35

trader
Member
Registered: 2008-03-03
Posts: 2

Help With Complex Fraction

Can someone please help me with this problem? I am stuck. The dotted lines are supposed to be solid lines. Thanks for any help. 

            4a
         ---------
         2a³ + 2
-------------------------
             8a
         ---------
          4a + 4

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#2 2008-03-03 07:49:26

Daniel123
Member
Registered: 2007-05-23
Posts: 663

Re: Help With Complex Fraction

I presume you want to simplify it?

Remembering that a fraction is the same as dividing,

When you divide by a fraction, it is the same as multiplying by the inverse of the fraction (i.e. the fraction flipped upside down). Therefore:

If you then multiply the top and the bottom and simplify, you will get:

Last edited by Daniel123 (2008-03-03 07:54:52)

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#3 2008-03-03 08:21:31

trader
Member
Registered: 2008-03-03
Posts: 2

Re: Help With Complex Fraction

Daniel, the answer the textbook gives is:   

         1/a² -a + 1

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#4 2008-03-03 08:27:27

mathsyperson
Moderator
Registered: 2005-06-22
Posts: 4,900

Re: Help With Complex Fraction

Daniel123 wrote:

From here, I get

.

By considering the polynomial division of (a³+1)/(a+1), you can then show that that is equal to

. To be honest though, I think it's simpler in its previous form.


Why did the vector cross the road?
It wanted to be normal.

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#5 2008-03-03 08:36:10

Daniel123
Member
Registered: 2007-05-23
Posts: 663

Re: Help With Complex Fraction

Whoops! I can see exactly what I've done. I was in the middle of writing my prefect application letter - so I wasn't paying much attention! sorry!

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#6 2008-03-03 09:19:09

trader
Member
Registered: 2008-03-03
Posts: 2

Re: Help With Complex Fraction

Thanks a lot guys. I appreciate the help.

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