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)`

Answer» `|z| = |z-4/z + 4/z| `
`<= |z-4/z| + |4/z|`
`|z| <= 2 + 4/|z| `
`=> |z| - 2 - 4/|z| <= 0`
`(|z|^2 - 2|z| -4)/|z| <= 0 `
roots are `|z = +- 2 + - (sqrt(4 +16))/2`
`= 1 +- sqrt5 `
`0 <= |z| <= 1 + sqrt5 `
max `|z| = 1 + sqrt(5 )`
option2 is correct


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