help again :S

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September 18th 2012, 08:10 AM
Petrus

help again :S

this one i got no ide what to do =S, i dont get it how i should do:
soulve the ekvation https://webwork.math.su.se/webwork2_...4caa0c5f21.pngThe solution should be of the form a+bi
September 18th 2012, 08:19 AM
Plato

Re: help again :S

Quote:

Originally Posted by Petrus

this one i got no ide what to do =S, i dont get it how i should do:
soulve the ekvation https://webwork.math.su.se/webwork2_...4caa0c5f21.pngThe solution should be of the form a+bi

$-13\text{Re}(z)=2~\&~15\text{Im}(z)=9$
September 18th 2012, 08:45 AM
Petrus

Re: help again :S

ehmm i dont get it...
September 18th 2012, 08:54 AM
Plato

Re: help again :S

Quote:

Originally Posted by Petrus

ehmm i dont get it...

Well the real part of the expression oh the left must equal the real part of the expression on the right.
Same idea for the imaginary parts.
September 18th 2012, 09:04 AM
Petrus

Re: help again :S

how can i see the re and im on z?
September 18th 2012, 09:14 AM
Plato

Re: help again :S

Quote:

Originally Posted by Petrus

how can i see the re and im on z?

If $z=a+bi$ then $\text{Re}(z)=a~\&~\text{Im}(z)=b$

$\text{Re}(2+9i)=2~\&~\text{Im}(2+9i)=9$

$\text{Re}(z-14\overline{z})=-13a~\&~\text{Im}(z-14\overline{z})=15b$
September 18th 2012, 09:24 AM
Petrus

Re: help again :S

a = -2/13 is correct
b = 9/15 is wrong ( acording to the computer program) what do i do wrong?
September 18th 2012, 09:49 AM
MarkFL

Re: help again :S

Try reducing 9/15...
September 18th 2012, 09:52 AM
Petrus

Re: help again :S

heheh ty ur best :D

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