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z=-1+sqrt3i , omega is complex number s...

`z=-1+sqrt3i , omega ` is complex number such that `abs(zomega)=1 , arg(z)-arg(w)=pi/2` .Find area of triangle made

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To find the area of the triangle formed by the points \( z \), \( \omega \), and the origin, we will follow these steps: ### Step 1: Identify the given complex number \( z \) Given: \[ z = -1 + \sqrt{3}i \] ### Step 2: Calculate the modulus of \( z \) The modulus of a complex number \( z = x + yi \) is given by: \[ |z| = \sqrt{x^2 + y^2} \] For \( z = -1 + \sqrt{3}i \): \[ |z| = \sqrt{(-1)^2 + (\sqrt{3})^2} = \sqrt{1 + 3} = \sqrt{4} = 2 \] ### Step 3: Find the complex number \( \omega \) We know that \( |z \cdot \omega| = 1 \). Therefore: \[ |z| \cdot |\omega| = 1 \implies |\omega| = \frac{1}{|z|} = \frac{1}{2} \] ### Step 4: Analyze the argument condition We are given that: \[ \arg(z) - \arg(\omega) = \frac{\pi}{2} \] This implies that the angle between \( z \) and \( \omega \) is \( 90^\circ \). Therefore, \( \omega \) is perpendicular to \( z \). ### Step 5: Determine the position of \( \omega \) Since \( z \) is in the second quadrant (as the real part is negative and the imaginary part is positive), \( \omega \) will be in the fourth quadrant due to the angle condition. ### Step 6: Calculate the coordinates of \( \omega \) Assuming \( \omega = x + yi \) and knowing \( |\omega| = \frac{1}{2} \): \[ \sqrt{x^2 + y^2} = \frac{1}{2} \implies x^2 + y^2 = \frac{1}{4} \] Given that \( \arg(z) - \arg(\omega) = \frac{\pi}{2} \), we can express \( \omega \) in terms of \( z \): \[ \omega = k(-\sqrt{3} - i) \quad \text{for some scalar } k \] To satisfy \( |\omega| = \frac{1}{2} \), we can find \( k \) such that: \[ |k| \cdot \sqrt{(-\sqrt{3})^2 + (-1)^2} = \frac{1}{2} \] Calculating the modulus: \[ \sqrt{3 + 1} = 2 \implies |k| \cdot 2 = \frac{1}{2} \implies |k| = \frac{1}{4} \] Thus, we can take \( k = \frac{1}{4} \): \[ \omega = \frac{1}{4}(-\sqrt{3} - i) = -\frac{\sqrt{3}}{4} - \frac{1}{4}i \] ### Step 7: Calculate the area of the triangle The area \( A \) of a triangle formed by points \( (0, 0) \), \( (x_1, y_1) \), and \( (x_2, y_2) \) can be calculated using the formula: \[ A = \frac{1}{2} \left| x_1y_2 - x_2y_1 \right| \] For our points: - \( z = (-1, \sqrt{3}) \) - \( \omega = \left(-\frac{\sqrt{3}}{4}, -\frac{1}{4}\right) \) Calculating the area: \[ A = \frac{1}{2} \left| (-1)(-\frac{1}{4}) - \left(-\frac{\sqrt{3}}{4}\right)(\sqrt{3}) \right| \] \[ = \frac{1}{2} \left| \frac{1}{4} + \frac{3}{4} \right| = \frac{1}{2} \left| 1 \right| = \frac{1}{2} \] ### Final Answer The area of the triangle formed by the points \( z \), \( \omega \), and the origin is: \[ \boxed{\frac{1}{2}} \]
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