1.

If `|z-4/z|=2`, then the maximum value of`|Z|`is equal to(1) `sqrt(3)+""1`(2) `sqrt(5)+""1`(3) 2(4) `2""+sqrt(2)`A. `sqrt3 + 1 `B. ` sqrt5 + 1 `C. `2`D. `2 + sqrt2`

Answer» Correct Answer - B
`|Z|= |(Z-(4)/(Z))+(4)/(Z)|le|Z-(4)/(Z)|+(4)/(|Z|) le 2 + (4)/(|Z|)`
`rArr |Z|^(2) - 2 |Z| - 4 le 0`
`rArr [|z| - sqrt(5) + 1)][(Z| - 1(-sqrt(5))]le 0`
`rArr 0 le |Z| le sqrt(5) + 1`


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