write \(\large (1-i)^{2i}\) as of the form x+iy
@ganeshie8 wanna try ?
@Loser66
\[\large (1-i)^{2i} = e^{2i \ln (1-i)}\]
how ?and sure :O when there is i im not sure of log or ln
lets hope it works... :) we can check wid wolfram in the end maybe
log z = ln r +i ( theta +2k pi)
ok
i never took complex analysis so idk from where u pulled up that formula
oh ok got it :)
from the notes there is box full of formulas xD
okay looks like the log thingy works : http://www.wolframalpha.com/input/?i=%281-i%29%5E%282i%29++%3D+e%5E%282i*ln%281-i%29%29
ok find somthing log z = ln |z| + i arg z
ok go ahead im doing this with music https://www.youtube.com/watch?v=fSKCJrh_VRc
\[\large (1-i)^{2i} = e^{2i \ln (1-i)} = e^{2i \ln \left(\sqrt{2}e^{i(\frac{-\pi}{4})}\right)}\]
fine so far ?
no , log e^z \(\neq\) z :\
but e^log z = z
why not
one of the properties
log e^z =z + i2k pi
well we're using the second property, so we should be fine ?
wolfram is fine wid this http://www.wolframalpha.com/input/?i=%281-i%29%5E%7B2i%7D+%3D+e%5E%7B2i+%5Cln+%281-i%29%7D++%3D++e%5E%7B2i+%5Cln+%5Cleft%28%5Csqrt%7B2%7De%5E%7Bi%28%5Cfrac%7B-%5Cpi%7D%7B4%7D%29%7D%5Cright%29%7D
ok keep going :O but i dont trust walfram sometimes
\[\large (1-i)^{2i} = e^{2i \ln (1-i)} = e^{2i \ln \left(\sqrt{2}e^{i(\frac{-\pi}{4})}\right)} = e^{2i \left[\ln \sqrt{2} - \frac{i\pi}{4}\right] }\]
nw we have to convert to x+iy
yes break them
r=2 theta=the rest ?
break it into two using product property of exponents : \(a^{m+n} = a^m.a^n\)
O.O
\[\large (1-i)^{2i} = e^{2i \ln (1-i)} = e^{2i \ln \left(\sqrt{2}e^{i(\frac{-\pi}{4})}\right)} = e^{2i \left[\ln \sqrt{2} - \frac{i\pi}{4}\right] } \] \[\large = e^{2i \ln \sqrt{2} } . e^ {2i\frac{-i\pi}{4}} = e^{i \ln 2 } . e^ {\frac{\pi}{2}} \]
ok then ?
we're done
\[\large (1-i)^{2i} = e^{2i \ln (1-i)} = e^{2i \ln \left(\sqrt{2}e^{i(\frac{-\pi}{4})}\right)} = e^{2i \left[\ln \sqrt{2} - \frac{i\pi}{4}\right] } \] \[\large = e^{2i \ln \sqrt{2} } . e^ {2i\frac{-i\pi}{4}} = e^{i \ln 2 } . e^ {\frac{\pi}{2}} \] \[ = e^ {\frac{\pi}{2}} \left[ \cos(\ln 2 ) + i\sin (\ln 2) \right] \]
ok lol i was confused , but nw only i got it xD ty !
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