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  1. Unit complex numbers with a Re-Im condition ●●●○○ 50 ptsHow many complex numbers zz satisfy the following two conditions: ∣z∣=1|z|=1 and Re⁡(z100)=Im⁡(z200)\operatorname{Re}\left(z^{100}\right)=\operatorname{Im}\left(z^{200}\right)?
  2. Count complex solutions of an exponential equation ●●●●○ 100 ptsHow many complex numbers zz such that ∣z∣<30\left| z \right| < 30 satisfy the equation ez=z−1z+1e^z = \frac{z - 1}{z + 1}?
  3. Smallest n with many solutions ●●●●○ 100 ptsLet f(x)=∣2{x}−1∣f(x)=|2\{x\}-1|, where {x}\{x\} denotes the fractional part of xx. Find the smallest positive integer nn such that the equation nf(xf(x))=xn f(x f(x))=x has at least 20122012 real solutions.