JEE Advanced2011MathematicsComplex NumberActual
If z is any complex number satisfying |z-3-2 i| 2 , then the maximum value of |2 z-6+5 i| is
Correct answer
5
Step-by-step solution
Given, |z-3-2 i| 2 To find minimum of |2 z-6+5 i| or 2 |z-3+ 5 2 i | Using triangle inequality, i.e. || z₁|-| z₂|| |z₁+z₂ | |z-3+ 5 2 i |= |z-3-2 i+2 i+ 5 2 i |= |(z-3-2 i)+ 9 2 i | || z-3-2 i |- 9 2 | |2- 9 2 | 5 2 |z-3+ 5 2 i | 5 2 or |2 z-6+5 i| 5