JEE Advanced2008MathematicsComplex NumberActual
Paragraph: Let A, B, C be three sets of complex numbers as defined below. A= z ; lm z 1 ; B= z:|z-2-i|=3 ; C= z: Re ((1-i) z)= 2 . Question: Let z be any point in A B C and let w be any point satisfying |w-2-i| < 3 . Then, |z|-|w|+3 lies between
Options
- A-6 and 3
- B-3 and 6
- C-6 and 6
- D-3 and 9
Correct answer
D. -3 and 9
Step-by-step solution
array ll & |w-(2+i)| < 3 & || w|-| 2+i|| < 3 & -3+ 5 < |w| < 3+ 5 & -3- 5 < -|w| < 3- 5 array Also, |z-(2+i)|=3 aligned -3+ 5 & |z| 3+ 5 -3 & < |z|-|w|+3 < 9 aligned