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Form the polynomial equation whose r...

Form the polynomial equation whose root are
`2 ,1 +- 3i`

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To form the polynomial equation whose roots are \(2\) and \(1 \pm 3i\), we will follow these steps: ### Step 1: Identify the roots The roots given are: - \(\alpha = 2\) - \(\beta = 1 + 3i\) - \(\gamma = 1 - 3i\) ### Step 2: Write the polynomial in factored form The polynomial can be expressed as: \[ (x - \alpha)(x - \beta)(x - \gamma) = 0 \] Substituting the values of the roots: \[ (x - 2)(x - (1 + 3i))(x - (1 - 3i)) = 0 \] ### Step 3: Simplify the complex roots First, we simplify the product of the complex conjugate roots: \[ (x - (1 + 3i))(x - (1 - 3i)) \] This can be rewritten using the difference of squares: \[ = (x - 1 - 3i)(x - 1 + 3i) = (x - 1)^2 - (3i)^2 \] Calculating \((3i)^2\): \[ (3i)^2 = 9i^2 = 9(-1) = -9 \] Thus, we have: \[ = (x - 1)^2 + 9 \] ### Step 4: Expand \((x - 1)^2 + 9\) Now, we expand \((x - 1)^2 + 9\): \[ (x - 1)^2 = x^2 - 2x + 1 \] So, \[ (x - 1)^2 + 9 = x^2 - 2x + 1 + 9 = x^2 - 2x + 10 \] ### Step 5: Combine with the real root Now we combine this with the real root: \[ (x - 2)(x^2 - 2x + 10) = 0 \] ### Step 6: Expand the polynomial Expanding the expression: \[ x(x^2 - 2x + 10) - 2(x^2 - 2x + 10) = 0 \] This gives: \[ x^3 - 2x^2 + 10x - 2x^2 + 4x - 20 = 0 \] Combining like terms: \[ x^3 - 4x^2 + 14x - 20 = 0 \] ### Final Polynomial Thus, the polynomial equation whose roots are \(2\) and \(1 \pm 3i\) is: \[ x^3 - 4x^2 + 14x - 20 = 0 \] ---
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