A procedure for finding the quadratic factors for the complex conjugate roots of a polynomial
with real coefficients.
![[x-(a+ib)][x-(a-ib)]=x^2+2ax+(a^2+b^2)=x^2+Bx+C.](/images/equations/BairstowsMethod/NumberedEquation1.svg) |
(1)
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Now write the original polynomial as
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(2)
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(3)
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(4)
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(5)
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(6)
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(7)
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(8)
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Now use the two-dimensional Newton's method to
find the simultaneous solutions.
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References
Press, W. H.; Flannery, B. P.; Teukolsky, S. A.; and Vetterling, W. T. Numerical
Recipes in FORTRAN: The Art of Scientific Computing, 2nd ed. Cambridge, England:
Cambridge University Press, pp. 277 and 283-284, 1989.Referenced
on Wolfram|Alpha
Bairstow's Method
Cite this as:
Weisstein, Eric W. "Bairstow's Method."
From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/BairstowsMethod.html
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