A) \[\sqrt{3}+1\]
B) \[\sqrt{5}+1\]
C) \[3\]
D) \[2+\sqrt{2}\]
Correct Answer: B
Solution :
[b]| Given, \[\left| z-\frac{4}{z} \right|=2\] |
| Now, \[\left| z \right|=\left| z-\frac{4}{z}+\frac{4}{z} \right|\le \left| z-\frac{4}{z} \right|+\left| \frac{4}{z} \right|\] |
| \[\Rightarrow \]\[\left| z \right|\le 2+\frac{4}{\left| z \right|}\] |
| \[\Rightarrow \]\[{{\left| z \right|}^{2}}-2\left| z \right|-4\le 0\] |
| \[\Rightarrow \]\[0\le \left| z \right|\le \sqrt{5}+1\] |
You need to login to perform this action.
You will be redirected in
3 sec
