Questions: Find all points of continuity of the given function: $f(z)=(Imz-Rez)^{-1}$
Solutions:
Let $z=x+iy$ where x,y are real numbers.
Then $f(z)=f(x,y)=(Im(x+iy)-Re(x+iy))^{-1}=(y-x)^{-1}=\frac{1}{y-x}$
The function is not valid when the denominator equals 0, that is, $y=x$.
Therefore, the function is discontinuous only at all points of the line $y=x$.
