What Are the Sum and Product of the Roots of This Complex Polynomial?

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SUMMARY

The discussion centers on the polynomial function p(z) = z^n + i z^{n-1} - 10 and the computation of the sum and product of its roots, denoted as Σω_j and Πω_j for j=1 to n. The example provided, f(x) = x^2 + 3x + 5, illustrates how the sum of the roots (a + b) and the product of the roots (ab) can be derived from the coefficients of the polynomial. The generalization of these concepts provides a framework for calculating the sum and product of roots for any polynomial of the form p(z).

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BlakeJA
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Question that I came across and that has stumped me for about a week hehe.
Let [tex]p(z)=z^n +i z^{n-1} - 10[/tex]

if [tex]\omega_j[/tex] are the roots for j=1,2,...,ncompute: [tex]\sum_{j=1}^n \omega_j}[/tex]

and

[tex]\prod_{j=1}^n \omega_j}[/tex]
 
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Let's consider an easier example first. Let f(x) = x^2 + 3x + 5. If f has roots a and b, then

x^2 + 3x + 5 = f(x) = (x - a)(x - b) = x^2 + x(-a - b) + ab.

Hence a + b and ab equal what? Now generalize.
 

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