Hi

How do i express a complex number in exact cartesian form?

for example:

(sqrt(3)+i)/((1-i)(sqrt(3)-i))

Whats the process?

thanks

phil

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- Jun 1st 2008, 05:26 AMtauruscomplex num to cartesian form
Hi

How do i express a complex number in exact cartesian form?

for example:

(sqrt(3)+i)/((1-i)(sqrt(3)-i))

Whats the process?

thanks

phil - Jun 1st 2008, 05:37 AMmr fantastic
- Jun 1st 2008, 05:59 AMtaurus
how do u expand the denominator because i get the following which is wrong:

sqrt(3) - i + sqrt(3)i - 1 - Jun 1st 2008, 06:09 AMmr fantastic
- Jun 1st 2008, 06:18 AMtaurus
and so the comples conjugate is:

as i just have to change the sign correct?

so i would get:

----------------------------------

How do i simplify that now? - Jun 1st 2008, 06:41 AMMoo
- Jun 1st 2008, 07:26 AMtaurus
heres another example i tried but looking at answer its not quite right:

((1-2i)/(3+4i)) - ((2+i)/5i)

so i first did subtraction of the top and bottom and got:

(-1-3i)/(3-1i)

I then performed division and got this:

((-3+3)/(9+1)) + ((-9+1)/(9+1))i

which simplifies to this:

0 + (-8/10)i

=> -4/5i

But that isint correct as the answer is -2/5

what am i doing wrong? - Jun 1st 2008, 07:45 AMGusbob
The question you gave was

This is two fractions with different denominators. If you recall your basic addition and subtraction of fractions, you don't subtract top and bottom. You need to make a common denominator first, and then subtract the top

Expand that and factorise, and you should get the answer.