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## #1 2008-12-14 19:48:26

ganesh
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### Complex Numbers - Pre University level I

1. What are the Real and Imaginary parts of the number 4 -i√3.

2. What is the conjugate of

?

3. If z=2 - i√3, then what is the value of
?

4. Express the following complex number in the forma + ib.

5. Find the real and imaginary parts of
.

6. If
,
find the conjugate of
.

Character is who you are when no one is looking.

## #2 2008-12-20 13:49:47

glenn101
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### Re: Complex Numbers - Pre University level I

1.
real part is 4
complex part is -i√3.
2.
the conjugate is
1/2+1/2*i
4.
5+5i   3+4i
------*------
3-4i    3+4i
= 15+20i+15i+20i^2
--------
25
= 15-20+20i+15i
-------
25
= -5+35i
------
25
= -1   7
---+---*i
5    5

Thats all I can do with my complex knowledge:)

"If your going through hell, keep going."

## #3 2008-12-20 21:45:57

ganesh
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### Re: Complex Numbers - Pre University level I

glenn101,
the only trivial mistake I noticed is in answer to 1, where when the real and imaginary parts are said, the imaginary part shouldn't include 'i'.
Well done!!!

Character is who you are when no one is looking.

## #4 2008-12-29 15:07:30

careless25
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### Re: Complex Numbers - Pre University level I

4. (-5 + 35i)/ 25

-0.2 + 1.4i

Edit: Oops!

Last edited by careless25 (2008-12-31 03:23:35)

ganesh
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