Complex numbers z and w satisfy |z|=|w|=1, |z+w|=√(2). What is the minimum value of P = |w-(4)/(z)+2(1+(w)/(z))i|?

Question

Complex numbers
`z` and
`w` satisfy
`|z|=|w|=1, |z+w|=√(2)`.

What is the minimum value of
`P = |w-(4)/(z)+2(1+(w)/(z))i|`?

Answer 1

Okay, here are the steps to find the minimum value of P:

1) Given: |z|=|w|=1 (z and w are complex numbers with unit modulus)

|z+w|=sqrt(2)

Find z and w such that these conditions are satisfied.

Possible solutions:

z = 1, w = i (or vice versa)

z = i, w = 1 (or vice versa)

2) Substitute into P = |w-\frac{4}{z}+2(1+\frac{w}{z})i|

For the cases:

z = 1, w = i: P = |-1-4+2(1+i)i| = |-5+2i| = sqrt(25+4) = 5

z = i, w = 1: P = |1-\frac{4}{i}+2(1+\frac{1}{i})i| = |-3+2i| = sqrt(9+4) = 5

3) The minimum value of P is 5.

So in summary, the minimum value of

P = |w-\frac{4}{z}+2(1+\frac{w}{z})i|

is 5.

Let me know if you have any other questions!