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What is the square root of 1/2-i(sqrt3)/...

What is the square root of `1/2-i(sqrt3)/(2)`?

A

`+-((sqrt3)/(2)+(i)/(2))`

B

`+-((sqrt3)/(2)-(i)/(2))`

C

`+-((1)/(2)-(sqrt(3))/(2))`

D

`+-((1)/(2)+i(sqrt(3))/(2))`

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The correct Answer is:
To find the square root of the complex number \( \frac{1}{2} - i \frac{\sqrt{3}}{2} \), we can follow these steps: ### Step 1: Set up the equation Let \( z = x + iy \) be the square root of \( \frac{1}{2} - i \frac{\sqrt{3}}{2} \). Therefore, we have: \[ z^2 = \frac{1}{2} - i \frac{\sqrt{3}}{2} \] ### Step 2: Square the expression Squaring \( z \) gives us: \[ (x + iy)^2 = x^2 + 2xyi - y^2 = (x^2 - y^2) + 2xyi \] Thus, we can equate the real and imaginary parts: \[ x^2 - y^2 = \frac{1}{2} \quad \text{(1)} \] \[ 2xy = -\frac{\sqrt{3}}{2} \quad \text{(2)} \] ### Step 3: Use the equations to find \( x^2 + y^2 \) We can use the identity: \[ x^2 + y^2 = (x^2 - y^2) + 2y^2 \] From equation (1), we know \( x^2 - y^2 = \frac{1}{2} \). We need to find \( x^2 + y^2 \). ### Step 4: Express \( y^2 \) in terms of \( x \) From equation (2), we can express \( y \) in terms of \( x \): \[ y = -\frac{\sqrt{3}}{4x} \] Now substituting \( y \) into \( x^2 + y^2 \): \[ y^2 = \left(-\frac{\sqrt{3}}{4x}\right)^2 = \frac{3}{16x^2} \] Thus, \[ x^2 + y^2 = x^2 + \frac{3}{16x^2} \] ### Step 5: Combine equations Now we can combine the equations: \[ x^2 + y^2 = \frac{1}{2} + 2y^2 \] Substituting \( y^2 \): \[ x^2 + \frac{3}{16x^2} = \frac{1}{2} + 2\left(\frac{3}{16x^2}\right) \] This simplifies to: \[ x^2 + \frac{3}{16x^2} = \frac{1}{2} + \frac{3}{8x^2} \] ### Step 6: Solve for \( x^2 \) Multiply through by \( 16x^2 \) to eliminate the fractions: \[ 16x^4 + 3 = 8x^2 + 6 \] Rearranging gives: \[ 16x^4 - 8x^2 - 3 = 0 \] Let \( u = x^2 \): \[ 16u^2 - 8u - 3 = 0 \] Using the quadratic formula: \[ u = \frac{-(-8) \pm \sqrt{(-8)^2 - 4 \cdot 16 \cdot (-3)}}{2 \cdot 16} \] \[ u = \frac{8 \pm \sqrt{64 + 192}}{32} \] \[ u = \frac{8 \pm \sqrt{256}}{32} = \frac{8 \pm 16}{32} \] This gives: \[ u = \frac{24}{32} = \frac{3}{4} \quad \text{or} \quad u = \frac{-8}{32} \quad \text{(not valid)} \] Thus, \( x^2 = \frac{3}{4} \) and \( x = \pm \frac{\sqrt{3}}{2} \). ### Step 7: Find \( y \) Using \( 2xy = -\frac{\sqrt{3}}{2} \): For \( x = \frac{\sqrt{3}}{2} \): \[ 2 \cdot \frac{\sqrt{3}}{2} \cdot y = -\frac{\sqrt{3}}{2} \implies y = -\frac{1}{2} \] For \( x = -\frac{\sqrt{3}}{2} \): \[ 2 \cdot -\frac{\sqrt{3}}{2} \cdot y = -\frac{\sqrt{3}}{2} \implies y = \frac{1}{2} \] ### Final Answer Thus, the square roots of the complex number are: \[ \frac{\sqrt{3}}{2} - \frac{1}{2}i \quad \text{and} \quad -\frac{\sqrt{3}}{2} + \frac{1}{2}i \]

To find the square root of the complex number \( \frac{1}{2} - i \frac{\sqrt{3}}{2} \), we can follow these steps: ### Step 1: Set up the equation Let \( z = x + iy \) be the square root of \( \frac{1}{2} - i \frac{\sqrt{3}}{2} \). Therefore, we have: \[ z^2 = \frac{1}{2} - i \frac{\sqrt{3}}{2} \] ...
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