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linuxux
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Homework Statement
Need to see if what I am doing is right, here is the problem:
z= 4i/(-1+i), express z^20 in standard form.
so,
z= 4i/(-1+i) = 2-2i
z^20 = 2*sqrt(2) x cis[20(-pi/4)] = 2*sqrt(2) x cis(-5pi)
= 2*sqrt(2) x [cos(-5pi) + i sin(-5pi)]
= 2*sqrt(2) x [-1 + 0i]
= 2*sqrt(2) x [-1] = -2048
so the final answer is only a real number of magnitude -2048+0i. is this correct? thanks.
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