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Write the conjugate of (-2-(1)/(3)i)^(3)...

Write the conjugate of `(-2-(1)/(3)i)^(3)`.

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To find the conjugate of the complex number \((-2 - \frac{1}{3}i)^3\), we will follow these steps: ### Step 1: Rewrite the complex number We start with the complex number: \[ z = -2 - \frac{1}{3}i \] ### Step 2: Factor out \(-1\) We can factor out \(-1\) from the expression: \[ z = -1 \left(2 + \frac{1}{3}i\right) \] ### Step 3: Cube the expression Now we will cube the expression: \[ z^3 = (-1)^3 \left(2 + \frac{1}{3}i\right)^3 = -1 \left(2 + \frac{1}{3}i\right)^3 \] ### Step 4: Use the binomial expansion Using the binomial expansion formula \((a + b)^3 = a^3 + 3a^2b + 3ab^2 + b^3\), where \(a = 2\) and \(b = \frac{1}{3}i\): \[ \left(2 + \frac{1}{3}i\right)^3 = 2^3 + 3 \cdot 2^2 \cdot \frac{1}{3}i + 3 \cdot 2 \cdot \left(\frac{1}{3}i\right)^2 + \left(\frac{1}{3}i\right)^3 \] ### Step 5: Calculate each term Calculating each term: - \(2^3 = 8\) - \(3 \cdot 2^2 \cdot \frac{1}{3}i = 3 \cdot 4 \cdot \frac{1}{3}i = 4i\) - \(3 \cdot 2 \cdot \left(\frac{1}{3}i\right)^2 = 3 \cdot 2 \cdot \frac{-1}{9} = -\frac{6}{9} = -\frac{2}{3}\) - \(\left(\frac{1}{3}i\right)^3 = \frac{1}{27}i^3 = -\frac{1}{27}i\) ### Step 6: Combine the terms Now, combine all the terms: \[ \left(2 + \frac{1}{3}i\right)^3 = 8 + 4i - \frac{2}{3} - \frac{1}{27}i \] To combine the real parts: \[ 8 - \frac{2}{3} = \frac{24}{3} - \frac{2}{3} = \frac{22}{3} \] And for the imaginary parts: \[ 4i - \frac{1}{27}i = \left(4 - \frac{1}{27}\right)i = \left(\frac{108}{27} - \frac{1}{27}\right)i = \frac{107}{27}i \] ### Step 7: Substitute back So we have: \[ \left(2 + \frac{1}{3}i\right)^3 = \frac{22}{3} + \frac{107}{27}i \] Thus, \[ z^3 = -\left(\frac{22}{3} + \frac{107}{27}i\right) = -\frac{22}{3} - \frac{107}{27}i \] ### Step 8: Find the conjugate The conjugate of a complex number \(a + bi\) is \(a - bi\). Therefore, the conjugate of \(z^3\) is: \[ \text{Conjugate} = -\frac{22}{3} + \frac{107}{27}i \] ### Final Answer Thus, the conjugate of \((-2 - \frac{1}{3}i)^3\) is: \[ -\frac{22}{3} + \frac{107}{27}i \] ---
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