Problem 1523 (difficulty: 3/10)

(a) \(\displaystyle \displaystyle\quad \re(z^2)=4\);    (b) \(\displaystyle \displaystyle\re\frac{z-1}{z+1}=0\);  (c) \(\displaystyle 0< \re (iz) < 2\pi\);  (d)

Give me another random problem!