For α,β,z∈ℂ and λ>1, if λ-1 is the radius of the circle |z-α|2+|z-β|2=2λ, then |α-β| is equal to _________. [2023]
(2)
For a circle, we have, |z-z1|2+|z-z2|2=|z1-z2|2
r=|z1-z2|2=|α-β|2=λ-1
Also, 2λ=|α-β|2
⇒2λ=4(λ-1)⇒2λ=4λ-4 ⇒2λ=4⇒λ=2
∴ |α-β|=2