Find the roots of each polynomial equations.
1. x^3-5x^2+2x+8=0
2. 2x^3+13x+17x-12=0
3. x^3-18x+27=0
4. x^3-2x^2-5x+6=0
5. x^3+x^2-5x+3=0

Question

Find the roots of each polynomial equations.
1. x^3-5x^2+2x+8=0
2. 2x^3+13x+17x-12=0
3. x^3-18x+27=0
4. x^3-2x^2-5x+6=0
5. x^3+x^2-5x+3=0

anonymous · Answer

well this is a lot of work

anonymous · Answer

:] just for geniuses like you!

anonymous · Answer

Dont worry    the only reason I am here is for helping..

anonymous · Answer

lets the first one

anonymous · Answer

the polynomial is complete, that is to say exponents  3, 2, 1, 0

anonymous · Answer

then you must get all the dividers of the independent term  =  8

anonymous · Answer

D(8) =  (+ or -) 8 , 4, 2, 1

anonymous · Answer

As you see there are 8 dividers

anonymous · Answer

Yes.

anonymous · Answer

we should replace every one instead of X, if you get ZERO after evaluating
we have a first root of the polynomial

anonymous · Answer

so  almost always you begin with   1

anonymous · Answer

(1)^3 - 5(1)^2 + 2(1) + 8   =  1 - 5 + 2 + 8  =  6     1 is not a root

anonymous · Answer

then   -1
      (-1)^3 - 5(-1)^2 + 2(-1) + 8 = -1 -5 -2 + 8 = 0        yes -1 is a root

anonymous · Answer

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