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Find the magnitude of (z̅ + z), z = 8i - 5 Where z is a complex number and z̅ is the conjugate of z

Find the magnitude of (z̅ + z), z = 8i - 5 Where z is a complex number and z̅ is the conjugate of z Correct Answer 10

Concept:

Conjugate of a complex number:

For any complex number z = x + iy  the conjugate z̅ is given by  z̅ = x - iy

Calculation:

z = 8i - 5 

z̅ = -8i - 5 

z̅ + z = -8i - 5 + 8i - 5 

z̅ + z = - 10

|z̅ + z| = |-10| = 10

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