Question 92878
Find all roots of the polynomial x cube-x squared+16x-16.
x^3-x^2+16x-16
Since the coefficients add up to zero x=1 is a root and x-1 is a factor.
Use synthetic division to find the other factors and roots.
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1)....1....-1....16....-16
.......1.....0.....16..|..0

Remainder is zero because 1 is a root.
Quotient is x^2+16
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Factoring x^2+16 you get (x+4i)(x-4i)
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All the roots are: x=1, x= 4i, x= -4i
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Cheers,
Stan H.