Question 177796: 14. find all the real and imaginary zeros of f(x)=x cubed+xsquared+13x-15; given that 1 is a zero of the function Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! find all the real and imaginary zeros of f(x)=x cubed+xsquared+13x-15; given that 1 is a zero of the function
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f(x) = x^3 +x^2 + 13x - 15
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Find the quotient when dividing f(x) by x-1:
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1)....1....1....13....-15
.......1....2....15...|..0
Quotient: x^2 + 2x + 15
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Find the zeroes of x^2 + 2x + 15
x = [-2 +- sqrt(4 - 4*1*15)]/2
x = [-2 +- sqrt(-56)]/2
x = [-2 +- 2sqrt(13)i]/2
x = -1 +- sqrt(13)i
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Cheers,
Stan H.
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