I saw a calculation by putting the opposite like: (-sqrt(2)-isqrt(2))^2, but I am not sure if I should do this one the same way.
i have just looked at the first one.
Hint:
\((-\sqrt2+i\sqrt2)^{100}=((-\sqrt2+i\sqrt2)^{2})^{50}\)
\((-\sqrt2+i\sqrt2)^{100}=((-\sqrt2+i\sqrt2)^{2})^{50}\\~\\ (-\sqrt2+i\sqrt2)^{2}=2-2-4i = -4i \)
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