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If z(1),z(2),z(3) are three complex numb...

If `z_(1),z_(2),z_(3)` are three complex numbers, such that `|z_(1)|=|z_(2)|=|z_(3)|=1` & `z_(1)^(2)+z_(2)^(2)+z_(3)^(2)=0` then `|z_(1)^(3)+z_(2)^(3)+z_(3)^(3)|` is equal to _______. (not equal to 1)

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To solve the problem, we start with the given conditions: 1. \( |z_1| = |z_2| = |z_3| = 1 \) 2. \( z_1^2 + z_2^2 + z_3^2 = 0 \) We need to find \( |z_1^3 + z_2^3 + z_3^3| \). ### Step-by-step Solution: **Step 1: Express \( z_1, z_2, z_3 \) in terms of a common complex number.** Since \( |z_1| = |z_2| = |z_3| = 1 \), we can express these complex numbers as: - \( z_1 = e^{i\theta_1} \) - \( z_2 = e^{i\theta_2} \) - \( z_3 = e^{i\theta_3} \) **Hint:** Use the fact that complex numbers on the unit circle can be expressed in exponential form. --- **Step 2: Use the condition \( z_1^2 + z_2^2 + z_3^2 = 0 \).** Substituting the expressions from Step 1: \[ e^{2i\theta_1} + e^{2i\theta_2} + e^{2i\theta_3} = 0 \] This implies that the angles \( 2\theta_1, 2\theta_2, 2\theta_3 \) are evenly spaced around the unit circle. Therefore, we can let: - \( 2\theta_1 = 0 \) - \( 2\theta_2 = \frac{2\pi}{3} \) - \( 2\theta_3 = \frac{4\pi}{3} \) Thus, we have: - \( z_1 = e^{i \cdot 0} = 1 \) - \( z_2 = e^{i \cdot \frac{2\pi}{3}} = \omega \) - \( z_3 = e^{i \cdot \frac{4\pi}{3}} = \omega^2 \) where \( \omega = e^{i \cdot \frac{2\pi}{3}} \) is a primitive cube root of unity. **Hint:** Recognize that the sum of the cube roots of unity is zero. --- **Step 3: Calculate \( z_1^3 + z_2^3 + z_3^3 \).** Using the property of cube roots of unity: \[ z_1^3 = 1^3 = 1, \quad z_2^3 = \omega^3 = 1, \quad z_3^3 = (\omega^2)^3 = 1 \] Thus, \[ z_1^3 + z_2^3 + z_3^3 = 1 + 1 + 1 = 3 \] **Hint:** Remember that \( \omega^3 = 1 \) for cube roots of unity. --- **Step 4: Find the modulus.** Since \( z_1^3 + z_2^3 + z_3^3 = 3 \), we have: \[ |z_1^3 + z_2^3 + z_3^3| = |3| = 3 \] ### Final Answer: The value of \( |z_1^3 + z_2^3 + z_3^3| \) is \( 3 \). ---

To solve the problem, we start with the given conditions: 1. \( |z_1| = |z_2| = |z_3| = 1 \) 2. \( z_1^2 + z_2^2 + z_3^2 = 0 \) We need to find \( |z_1^3 + z_2^3 + z_3^3| \). ### Step-by-step Solution: ...
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