If z=x+iy, xy 0, satisfies the equation z2+i z=0, then |z2 | is equal to :
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Answer
(4) 1
Solution
z2=-i z
Taking modulus: |z|2=|i| | z|=|z|
|z| (|z|-1 )=0
xy 0 z 0 |z|=1
|z2 |=|z|2=1
Answer: (4)
If z=x+iy, xy 0, satisfies the equation z2+i z=0, then |z2 | is equal to :
(4) 1
z2=-i z
Taking modulus: |z|2=|i| | z|=|z|
|z| (|z|-1 )=0
xy 0 z 0 |z|=1
|z2 |=|z|2=1
Answer: (4)
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