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If (3/2+(isqrt(3))/2)^(50)=3^(25)(x+iy),...

If `(3/2+(isqrt(3))/2)^(50)=3^(25)(x+iy)`, where x and y are reals, then the ordered pair (x,y) is given by

A

(0,3)

B

`(1//2,sqrt(3)//2)`

C

`(-3,0)`

D

`(0,-3)`

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The correct Answer is:
To solve the problem, we start with the equation: \[ \left(\frac{3}{2} + i\frac{\sqrt{3}}{2}\right)^{50} = 3^{25}(x + iy) \] ### Step 1: Rewrite the base in polar form The complex number \(\frac{3}{2} + i\frac{\sqrt{3}}{2}\) can be expressed in polar form. We first find the modulus \(r\) and the argument \(\theta\). The modulus \(r\) is given by: \[ r = \sqrt{\left(\frac{3}{2}\right)^2 + \left(\frac{\sqrt{3}}{2}\right)^2} = \sqrt{\frac{9}{4} + \frac{3}{4}} = \sqrt{3} \] The argument \(\theta\) is given by: \[ \theta = \tan^{-1}\left(\frac{\frac{\sqrt{3}}{2}}{\frac{3}{2}}\right) = \tan^{-1}\left(\frac{\sqrt{3}}{3}\right) = \frac{\pi}{6} \] Thus, we can express the complex number in polar form as: \[ \frac{3}{2} + i\frac{\sqrt{3}}{2} = \sqrt{3} \left(\cos\frac{\pi}{6} + i\sin\frac{\pi}{6}\right) \] ### Step 2: Apply De Moivre's Theorem Using De Moivre's Theorem, we can raise the polar form to the 50th power: \[ \left(\sqrt{3}\right)^{50} \left(\cos\left(50 \cdot \frac{\pi}{6}\right) + i\sin\left(50 \cdot \frac{\pi}{6}\right)\right) \] Calculating the modulus: \[ \left(\sqrt{3}\right)^{50} = 3^{25} \] Now, we calculate the angle: \[ 50 \cdot \frac{\pi}{6} = \frac{50\pi}{6} = \frac{25\pi}{3} \] To simplify \(\frac{25\pi}{3}\), we can subtract \(8\pi\) (which is \(2\cdot 4\pi\)): \[ \frac{25\pi}{3} - 8\pi = \frac{25\pi - 24\pi}{3} = \frac{\pi}{3} \] ### Step 3: Substitute back into the equation Now we can substitute back into our expression: \[ 3^{25} \left(\cos\frac{\pi}{3} + i\sin\frac{\pi}{3}\right) \] Calculating \(\cos\frac{\pi}{3}\) and \(\sin\frac{\pi}{3}\): \[ \cos\frac{\pi}{3} = \frac{1}{2}, \quad \sin\frac{\pi}{3} = \frac{\sqrt{3}}{2} \] Thus, we have: \[ 3^{25} \left(\frac{1}{2} + i\frac{\sqrt{3}}{2}\right) \] ### Step 4: Equate and find \(x\) and \(y\) Now we equate this to \(3^{25}(x + iy)\): \[ 3^{25} \left(\frac{1}{2} + i\frac{\sqrt{3}}{2}\right) = 3^{25}(x + iy) \] Dividing both sides by \(3^{25}\): \[ \frac{1}{2} + i\frac{\sqrt{3}}{2} = x + iy \] From this, we can directly read off the values of \(x\) and \(y\): \[ x = \frac{1}{2}, \quad y = \frac{\sqrt{3}}{2} \] ### Final Answer The ordered pair \((x, y)\) is: \[ \left(\frac{1}{2}, \frac{\sqrt{3}}{2}\right) \]

To solve the problem, we start with the equation: \[ \left(\frac{3}{2} + i\frac{\sqrt{3}}{2}\right)^{50} = 3^{25}(x + iy) \] ### Step 1: Rewrite the base in polar form ...
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