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Given the complex number z= (-1 + sqrt3i...

Given the complex number `z= (-1 + sqrt3i)/(2) and w= (-1- sqrt3i)/(2)` (where `i= sqrt-1`)
Calculate the modulus and argument of w and z

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To solve the problem of finding the modulus and argument of the complex numbers \( z \) and \( w \), we proceed as follows: Given: \[ z = \frac{-1 + \sqrt{3}i}{2} \] \[ w = \frac{-1 - \sqrt{3}i}{2} \] ### Step 1: Calculate the modulus of \( z \) The modulus of a complex number \( z = x + yi \) is given by: \[ |z| = \sqrt{x^2 + y^2} \] For \( z \), we have: - \( x = -\frac{1}{2} \) - \( y = \frac{\sqrt{3}}{2} \) Now, we calculate: \[ |z| = \sqrt{\left(-\frac{1}{2}\right)^2 + \left(\frac{\sqrt{3}}{2}\right)^2} \] \[ = \sqrt{\frac{1}{4} + \frac{3}{4}} = \sqrt{1} = 1 \] ### Step 2: Calculate the argument of \( z \) The argument of a complex number \( z = x + yi \) is given by: \[ \theta = \tan^{-1}\left(\frac{y}{x}\right) \] For \( z \): \[ \theta_z = \tan^{-1}\left(\frac{\frac{\sqrt{3}}{2}}{-\frac{1}{2}}\right) = \tan^{-1}(-\sqrt{3}) \] The value of \( \tan^{-1}(-\sqrt{3}) \) corresponds to an angle in the second quadrant (since \( x < 0 \) and \( y > 0 \)): \[ \theta_z = \frac{2\pi}{3} \quad \text{(in radians)} \] ### Step 3: Calculate the modulus of \( w \) Using the same formula for modulus: \[ |w| = \sqrt{x^2 + y^2} \] For \( w \): - \( x = -\frac{1}{2} \) - \( y = -\frac{\sqrt{3}}{2} \) Now, we calculate: \[ |w| = \sqrt{\left(-\frac{1}{2}\right)^2 + \left(-\frac{\sqrt{3}}{2}\right)^2} \] \[ = \sqrt{\frac{1}{4} + \frac{3}{4}} = \sqrt{1} = 1 \] ### Step 4: Calculate the argument of \( w \) For \( w \): \[ \theta_w = \tan^{-1}\left(\frac{-\frac{\sqrt{3}}{2}}{-\frac{1}{2}}\right) = \tan^{-1}(\sqrt{3}) \] The value of \( \tan^{-1}(\sqrt{3}) \) corresponds to an angle in the first quadrant: \[ \theta_w = \frac{\pi}{3} \quad \text{(in radians)} \] ### Final Results - Modulus of \( z \): \( |z| = 1 \) - Argument of \( z \): \( \theta_z = \frac{2\pi}{3} \) - Modulus of \( w \): \( |w| = 1 \) - Argument of \( w \): \( \theta_w = \frac{\pi}{3} \)
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ICSE-COMPLEX NUMBERS-Exercise (D)
  1. Find the modulus and amplitude of the following complex numbers and he...

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  2. Find the modulus and amplitude of the following complex numbers and he...

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  3. Find the modulus and amplitude of the following complex numbers and he...

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  4. Find the modulus and amplitude of the following complex numbers and he...

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  5. Find the modulus and amplitude of the following complex numbers and he...

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  6. Find the modulus and amplitude of the following complex numbers and he...

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  7. Find the modulus and amplitude of the following complex numbers and he...

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  8. Find the modulus and amplitude of the following complex numbers and he...

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  9. Find the modulus and amplitude of the following complex numbers and he...

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  10. Find the modulus and amplitude of the following complex numbers and he...

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  11. Find the modulus and amplitude of the following complex numbers and he...

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  12. Find the modulus and amplitude of the following complex numbers and he...

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  13. Change the following complex numbers into polar form -4+4 sqrt3i

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  14. Change the following complex numbers into polar form (1+ 3i)/(1-2i)

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  15. Change the following complex numbers into polar form (1+ 2i)/(1-(1-...

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  16. Change the following complex numbers into polar form (1+ 7i)/((2-i)...

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  17. Given the complex number z= (-1 + sqrt3i)/(2) and w= (-1- sqrt3i)/(2) ...

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  18. Given the complex number z= (-1 + sqrt3i)/(2) and w= (-1- sqrt3i)/(2) ...

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  19. Given the complex number z= (-1 + sqrt3i)/(2) and w= (-1- sqrt3i)/(2) ...

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  20. Given the complex number z= (-1 + sqrt3i)/(2) and w= (-1- sqrt3i)/(2) ...

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