1)、2/z+i-(z+1)=2/(1-2i+i)-(1-2i+1)=2/(1-i)-(2-2i)
=1+i-2+2i=-1+3i
∴ω=-1-3i
2)、|az-i|/√(a+1)=│(a-2ai-i)│√(a+1)
=√[a^2+(2a+1)^2]/√(a+1)=√[(5a^2+4a+1)/(a+1)]≥√2/2
∴(5a^2+4a+1)/(a+1)]≥1/2
即(10a^2+7a+1)/(a+1)≥0,
(5a+1)(2a+1)/(a+1)≥0
∴-1<a≤-1/2,或a≥-1/5
1)、2/z+i-(z+1)=2/(1-2i+i)-(1-2i+1)=2/(1-i)-(2-2i)
=1+i-2+2i=-1+3i
∴ω=-1-3i
2)、|az-i|/√(a+1)=│(a-2ai-i)│√(a+1)
=√[a^2+(2a+1)^2]/√(a+1)=√[(5a^2+4a+1)/(a+1)]≥√2/2
∴(5a^2+4a+1)/(a+1)]≥1/2
即(10a^2+7a+1)/(a+1)≥0,
(5a+1)(2a+1)/(a+1)≥0
∴-1<a≤-1/2,或a≥-1/5