Rez=1-cost ,Imz=sint
lzl=√[(1-cost)²+sin²t=√(1-2cost+cos²t+sin²t)=√(2-2cost)=√2*(1-cost)=√2(1-cos²t/2+sin²t/2)=√2*2sin²t/2=2sint/2
1-cost=1-(cos²t/2-sin²t/2)=sin²t/2+sin²t/2=2sin²t/2
cosФ=Rez/lzl=2sin²t/2/2sint/2=sint/2=cos(π/2-t)
sinФ=Imz/lzl=sint/2sint2=2sint/2*cost/2/2sint/2=cost/2=sin(π/2-t/2)
z=cos(π/2-t/2)+isin(π/2-t/2)
