SOLUTION: find all zeroes f(x) = x^3-11x+150

Question 310457: find all zeroes f(x) = x^3-11x+150
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
find all zeroes f(x) = x^3-11x+150
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I graphed it to find one zero at x = -6.
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Use synthetic division to help find the other zeroes:
-6)....1....0....-11....150
.......1....-6....25....|..0
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Quotient: x^2-6x+25
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Solve x^2-6x+25 = 0
x = [6 +- sqrt(36-4*1*25)]/2
x = [6 +- sqrt(-64)]/2
x = [3 +- 4i]
x = 3+4i or x = 3-4i
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Cheers,
Stan H.
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