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The roots of x^(2)-7ix-12=0 are . . . A...

The roots of `x^(2)-7ix-12=0` are . . . And . . . .

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To find the roots of the quadratic equation \( x^2 - 7ix - 12 = 0 \), we will use the quadratic formula: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] ### Step 1: Identify coefficients In the equation \( x^2 - 7ix - 12 = 0 \), we identify the coefficients: - \( a = 1 \) - \( b = -7i \) - \( c = -12 \) ### Step 2: Substitute coefficients into the quadratic formula Now we substitute these values into the quadratic formula: \[ x = \frac{-(-7i) \pm \sqrt{(-7i)^2 - 4 \cdot 1 \cdot (-12)}}{2 \cdot 1} \] ### Step 3: Simplify the expression This simplifies to: \[ x = \frac{7i \pm \sqrt{(-7i)^2 + 48}}{2} \] ### Step 4: Calculate \( b^2 \) Now, we calculate \( (-7i)^2 \): \[ (-7i)^2 = 49i^2 = 49(-1) = -49 \] ### Step 5: Substitute back into the equation Substituting this back into our expression gives: \[ x = \frac{7i \pm \sqrt{-49 + 48}}{2} \] ### Step 6: Simplify under the square root Now simplify under the square root: \[ -49 + 48 = -1 \] Thus, we have: \[ x = \frac{7i \pm \sqrt{-1}}{2} \] ### Step 7: Substitute \( \sqrt{-1} \) with \( i \) Since \( \sqrt{-1} = i \), we can write: \[ x = \frac{7i \pm i}{2} \] ### Step 8: Separate the two cases This gives us two cases: 1. \( x = \frac{7i + i}{2} = \frac{8i}{2} = 4i \) 2. \( x = \frac{7i - i}{2} = \frac{6i}{2} = 3i \) ### Final Roots Thus, the roots of the equation \( x^2 - 7ix - 12 = 0 \) are: \[ x = 4i \quad \text{and} \quad x = 3i \]
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