If $$|z-2|=|z-1|$$, where $$z$$ is a complex number, then locus $$z$$ is a straight line

If $${\left( {{{1 + i} \over {1 - i}}} \right)^m} = 1$$, then m cannot be equal to

$$(\sin \theta-i \cos \theta)^3$$ is equal to

Real part of $$(\cos 4+i \sin 4+1)^{2020}$$ is