If α and β are different complex numbers with |β|=1 then find ∣∣β−α1−¯αβ∣∣
Here α and β are different complex numbers such that |β|=1
∣∣β−α1−¯αβ∣∣2
=∣∣β−α1−¯αβ∣∣[¯¯¯¯¯¯¯¯¯β−α¯¯¯¯¯¯¯¯¯¯¯¯1−¯αβ] [∵ |z|2=z¯z]
=[β−α1−¯αβ][¯β−¯α1−αβ]
=β¯β−β¯α−α¯β+α¯α1−¯αβ−α¯β+α¯αβ¯β
=|β|2−¯αβ−α¯β+|α|21−¯αβ−α¯β+|α|2|β|2
=1−¯αβ−α¯β+|α|21−¯αβ−¯αβ+|α|2=1
∴ ∣∣β−α1−αβ∣∣=1