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December 15th, 2012, 07:31 AM   #1
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Help complex numbers

Need help about this:

Express the following in the form :

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December 15th, 2012, 07:59 AM   #2
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Re: Help complex numbers

Try multiplying both terms by 1 in the form of the conjugate of the denominator over itself. Then add the resulting real and imaginary components. What do you get?
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December 15th, 2012, 08:11 AM   #3
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Re: Help complex numbers

I get this: 4-4/3i , but I'm not sure that it is right:/
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December 15th, 2012, 08:26 AM   #4
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Re: Help complex numbers

No, that's not correct. Can you post your work so we can see where you are making an error?
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December 15th, 2012, 08:51 AM   #5
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Re: Help complex numbers

No, it says it have very large size ( can you post your?
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December 15th, 2012, 09:20 AM   #6
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Re: Help complex numbers

Type it out (should only take a minute or two at the most). I would much rather see typed work than images of handwritten work anyway.
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December 15th, 2012, 09:09 PM   #7
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Re: Help complex numbers

1-3i/1+i - i/2+i=
(1-3i)(-2-i)+(-i)(1+i) / (1+i)(-2-i)
= (-5+5i)+(-i+1) / -1-3i
= -5+5i-i+1 / -1-3i
= -4+4i / -1-3i
= 4 - 4/3 i
Re= 4, Im= -4/3i
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December 15th, 2012, 09:15 PM   #8
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Re: Help complex numbers

I suggest simplifying:

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December 15th, 2012, 10:52 PM   #9
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Re: Help complex numbers

I get this after simplyfing:
-2-4i/2 - 2i+1/5
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December 15th, 2012, 11:05 PM   #10
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Re: Help complex numbers

If you mean (-2-4i)/2 - (2i+1)/5 then that is correct. This can further be simplified to:



Now you need collect together the real and imaginary parts.
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