SOLUTION: Find all the rational zeros of the function. f(x) = x3 – 19x – 30

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Question 528095: Find all the rational zeros of the function. f(x) = x3 – 19x – 30
Answer by lwsshak3(11628) About Me  (Show Source):
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Find all the rational zeros of the function. f(x) = x3 – 19x – 30
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Using the Rational Roots Theorem
...0...|...1......0......-19.......-30...........
...1...|...1......1......-18.......-48...........
...2...|...1......2......-15.......-60............
...3 ..|...1..... 3......-10.......-60.............
...4. .|...1......4.......-3........-18........
...5...|...1......5........6............0 (5 is a root)
(x-5)(x^2+5x+6)
(x-5)(x+2)(x+3)
ans:
zeros are: -3, -2 and 5