Let |z-3+2i| ≤ 4 , then the absolute different between the maximum and minimum values of |z| is
Let C = 3 - 2i be the centre of the circle |z-3+2i|= 4 . Join the origin to C and let it meet the circle in A and B (see figure) .
Least value of |z| = OB
= CB - OC
= 4 - √32+22
= 4 - √13
Maximim value of |z| = OA = 4 + √13
The absolute difference between the maximum and minimum values of |z| is 2 √13