find (3-3i)^6
1) find (3-3i)^2 2) find ((3-3i)^2)^3
Are you solving this using De Moivre's Theorem and stuff like that? Here is how I would start it off, \[\Large\bf\sf (3-3\mathcal i)^6\quad=\quad \left(3\sqrt2\right)^6\left(\frac{\sqrt2}{2}-\frac{\sqrt{2}}{2}\mathcal i\right)^6\] \[\Large\bf\sf =\quad \left(3\sqrt2\right)^6\left(\cos\left[-\frac{\pi}{4}\right]-\mathcal i\sin\left[-\frac{\pi}{4}\right]\right)^6\]
yea
Then applying De Moivre's Theorem,\[\Large\bf\sf =\quad \left(3\sqrt2\right)^6\left(\cos\left[-\frac{6\pi}{4}\right]-\mathcal i\sin\left[-\frac{6\pi}{4}\right]\right)\]Simplifies,\[\Large\bf\sf =\quad \left(3\sqrt2\right)^6\left(\cos\left[-\frac{3\pi}{2}\right]-\mathcal i\sin\left[-\frac{3\pi}{2}\right]\right)\]From there you can simplfy the sine and cosine.
Any confusion on the factoring that I did as the first step? That part can be a lil tricky.
um naw it seems good
\[\left( 1-\iota \right)^2=1+\iota^2-2\iota=1-1-2\iota=-2\iota \] \[\left( 1-\iota \right)^6=\left\{ \left( 1-\iota \right)^2 \right\}^3=\left( -2\iota \right)^3=-8*\iota^2*\iota=-8*-1*\iota=8\iota \] \[\left( 3-3\iota \right)^6=3^6\left( 1-\iota \right)^6=3^6*8\iota=?\]
Ooo I made a boo boo in a few of my steps... blah. When I converted to sine and cosine, all of those should be + sine, not minus.
Hmm ok good we seem to be getting the same answer,\[\Large\bf\sf 3^6\cdot 8\mathcal i\]
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i think there is something wrong in your second line in the beginning. i may be wrong. i think it should be\[\left( 3\sqrt{2} \right)^6\left\{ \cos (\frac{- \pi }{ 4 })+\iota \sin \left( \frac{- \pi }{ 4 } \right) \right\}^{6}\]
Yes I mentioned that :p
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