Question 233419
The expression(-1+i)^3 is equivalent to 
(1) -3i
(2) -2-2i
(3) -1-i
(4) 2+2i
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(-1+i)^2 = 1-1 - 2i = -2i
(-1+i)^3 = -2i*(-1+i) = 2i + 2
= 2+2i --> #4
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-1+i = sqrt(2)cis135
(-1+i)^3 = 2sqrt(2)cis405
= 2sqrt(2)cis45
= 2sqrt(2)*(cos(45) + isin(45))
= 2 + 2i  Same answer