f(-1) = - 1 - 10 - 13 + 24 = 0
Thus x - (- 1) = x + 1 is a factor.
To find other factors use synthetic division:-
_|1 __-10__13__24
-1|____-1__11_-24
_|1__- 11__24__0
(x + 1)(x² - 11x + 24) = 0
(x + 1)(x - 8)(x - 3) = 0
x = - 1 , x = 8 , x = 3
2007-11-20 20:35:25
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answer #1
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answered by Como 7
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3 is a root of the equation, because when you put x=3 the result is 0.
So we divide it by (x-3):
(x^3 - 10x^2 + 13x + 24) : (x-3)
=
(x-3)*(x^2-7x-8)
which can then be broken down further into:
(x-3)*(x+1)*(x-8)
So x is either 3, -1 or 8.
I hope this helped.
Please don't forget to put my answer as best answer, thank you!
2007-11-20 20:10:03
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answer #2
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answered by Sir Rogers 2
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x^3 --10x^2 + 13x + 24 = 0
=> x^3 -- 3x^2 -- 7x^2 + 21x -- 8x + 24 = 0
=> x^2(x -- 3) -- 7x(x -- 3) -- 8(x -- 3) = 0
=> (x -- 3)(x^2 -- 7x -- 8) = 0 giving x = 3 answer (1).
=> x^2 -- 7x -- 8 = 0
=> (x -- 8)(x + 1) = 0 giving x = 8, --1. answers(2,3).
whencw x = 3, 8, --1.
2007-11-20 20:05:34
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answer #3
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answered by sv 7
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x³ - 10x² + 13x + 24 = 0
x³ - 3x² - 7x² + 21x - 8x + 24 = 0
(x²)(x - 3) - (7x)(x - 3) - (8)(x - 3) = 0
(x - 3)( x² - 7x - 8) = 0
(x - 3) (x - 8) (x +1) = 0
So,
x = 3, 8, -1
2007-11-20 20:13:50
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answer #4
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answered by rnygelle87 2
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Answers are -1 and 3.
2007-11-20 20:03:19
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answer #5
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answered by Anonymous
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Use synthetic division followed by the quadratic equation (if necessary).
2007-11-20 20:00:23
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answer #6
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answered by Anonymous
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