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Find the square roots of the following:`-8\- 6i`

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To find the square roots of the complex number \(-8 - 6i\), we will follow these steps: ### Step 1: Assume the square root Let the square root of \(-8 - 6i\) be \(z = a + bi\), where \(a\) and \(b\) are real numbers. ### Step 2: Square both sides Squaring both sides gives us: \[ z^2 = (a + bi)^2 = a^2 + 2abi - b^2 \] This can be rewritten as: \[ z^2 = (a^2 - b^2) + (2ab)i \] We want this to equal \(-8 - 6i\). ### Step 3: Set up equations From the above expression, we can equate the real and imaginary parts: 1. \(a^2 - b^2 = -8\) (real part) 2. \(2ab = -6\) (imaginary part) ### Step 4: Solve for \(b\) From the second equation \(2ab = -6\), we can express \(b\) in terms of \(a\): \[ b = \frac{-6}{2a} = \frac{-3}{a} \] ### Step 5: Substitute \(b\) into the first equation Substituting \(b\) into the first equation gives: \[ a^2 - \left(\frac{-3}{a}\right)^2 = -8 \] This simplifies to: \[ a^2 - \frac{9}{a^2} = -8 \] Multiplying through by \(a^2\) to eliminate the fraction: \[ a^4 + 8a^2 - 9 = 0 \] ### Step 6: Let \(x = a^2\) Let \(x = a^2\). Then we have: \[ x^2 + 8x - 9 = 0 \] We can solve this quadratic equation using the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} = \frac{-8 \pm \sqrt{8^2 - 4 \cdot 1 \cdot (-9)}}{2 \cdot 1} \] Calculating the discriminant: \[ x = \frac{-8 \pm \sqrt{64 + 36}}{2} = \frac{-8 \pm \sqrt{100}}{2} = \frac{-8 \pm 10}{2} \] This gives us two solutions: 1. \(x = 1\) 2. \(x = -9\) (not valid since \(x = a^2\) must be non-negative) ### Step 7: Find \(a\) Since \(x = a^2 = 1\), we have: \[ a = \pm 1 \] ### Step 8: Find \(b\) Now, substituting \(a\) back to find \(b\): - If \(a = 1\): \[ b = \frac{-3}{1} = -3 \] - If \(a = -1\): \[ b = \frac{-3}{-1} = 3 \] ### Step 9: Write the square roots Thus, the square roots of \(-8 - 6i\) are: \[ 1 - 3i \quad \text{and} \quad -1 + 3i \] We can express this as: \[ \sqrt{-8 - 6i} = \pm(1 - 3i) \] ### Final Answer The square roots of \(-8 - 6i\) are: \[ 1 - 3i \quad \text{and} \quad -1 + 3i \] ---

To find the square roots of the complex number \(-8 - 6i\), we will follow these steps: ### Step 1: Assume the square root Let the square root of \(-8 - 6i\) be \(z = a + bi\), where \(a\) and \(b\) are real numbers. ### Step 2: Square both sides Squaring both sides gives us: \[ ...
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