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If |z + omega|^(2) = |z|^(2)+|omega|^(2...

If ` |z + omega|^(2) = |z|^(2)+|omega|^(2)`, where z and ` omega ` are complex numbers , then

A

`z/omega ` is purely real

B

`z/omega` is purely imaginary

C

`zbaromega + barz omega =0`

D

` amp ( z/omega) = pi/2`

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AI Generated Solution

The correct Answer is:
To solve the problem, we start with the given equation: \[ |z + \omega|^2 = |z|^2 + |\omega|^2 \] where \( z \) and \( \omega \) are complex numbers. ### Step 1: Express \( z \) and \( \omega \) Let \( z = x + iy \) where \( x \) and \( y \) are real numbers. We are also given that \( \omega = \frac{1}{2} + i \frac{\sqrt{3}}{2} \). ### Step 2: Calculate \( |z|^2 \) and \( |\omega|^2 \) The modulus squared of \( z \) is calculated as: \[ |z|^2 = x^2 + y^2 \] For \( \omega \): \[ |\omega|^2 = \left(\frac{1}{2}\right)^2 + \left(\frac{\sqrt{3}}{2}\right)^2 = \frac{1}{4} + \frac{3}{4} = 1 \] ### Step 3: Substitute into the equation Now substitute these values back into the original equation: \[ |z + \omega|^2 = |z|^2 + |\omega|^2 \implies |z + \omega|^2 = x^2 + y^2 + 1 \] ### Step 4: Calculate \( |z + \omega|^2 \) Now calculate \( z + \omega \): \[ z + \omega = \left(x + \frac{1}{2}\right) + i\left(y + \frac{\sqrt{3}}{2}\right) \] Now, we find the modulus squared: \[ |z + \omega|^2 = \left(x + \frac{1}{2}\right)^2 + \left(y + \frac{\sqrt{3}}{2}\right)^2 \] ### Step 5: Expand and set the equation Expanding this gives: \[ \left(x + \frac{1}{2}\right)^2 = x^2 + x + \frac{1}{4} \] \[ \left(y + \frac{\sqrt{3}}{2}\right)^2 = y^2 + y\sqrt{3} + \frac{3}{4} \] Combining these, we have: \[ |z + \omega|^2 = x^2 + y^2 + x + y\sqrt{3} + 1 \] ### Step 6: Set the two expressions equal Now we set the two expressions for \( |z + \omega|^2 \) equal to each other: \[ x^2 + y^2 + x + y\sqrt{3} + 1 = x^2 + y^2 + 1 \] ### Step 7: Simplify Subtract \( x^2 + y^2 + 1 \) from both sides: \[ x + y\sqrt{3} = 0 \] ### Step 8: Rearranging From this, we can express: \[ x = -y\sqrt{3} \] ### Step 9: Find the ratio \( \frac{z}{\omega} \) Now, we need to find \( \frac{z}{\omega} \): \[ \frac{z}{\omega} = \frac{x + iy}{\frac{1}{2} + i\frac{\sqrt{3}}{2}} = \frac{2(x + iy)}{1 + i\sqrt{3}} \] ### Step 10: Rationalize the denominator To rationalize: \[ \frac{2(x + iy)(1 - i\sqrt{3})}{(1 + i\sqrt{3})(1 - i\sqrt{3})} = \frac{2((x + iy)(1 - i\sqrt{3}))}{1 + 3} = \frac{2((x + iy)(1 - i\sqrt{3}))}{4} \] ### Step 11: Simplify This simplifies to: \[ \frac{(x + iy)(1 - i\sqrt{3})}{2} \] ### Step 12: Substitute \( x = -y\sqrt{3} \) Substituting \( x = -y\sqrt{3} \): \[ \frac{(-y\sqrt{3} + iy)(1 - i\sqrt{3})}{2} \] ### Conclusion This shows that \( \frac{z}{\omega} \) is purely imaginary, confirming that the argument \( \frac{z}{\omega} \) is \( \frac{\pi}{2} \).
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