SOLUTION: Solving the equation in the real number system. x^4-3x^3+5x^2-x-10=0

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Question 1046255: Solving the equation in the real number system. x^4-3x^3+5x^2-x-10=0
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
Possible roots to try using synthetic division are -10,-5,-2,-1,1,2,5,10.
-1  |    1   -3   5   -1   -10
    |
    |        -1   4    -9   10
    |___________________________________
        1    -4   9   -10    0


2   |   1    -4    9    -10   
    |    
    |         2    -4    10  
    |__________________________________
         1    -2   5     0

Both -1 and +2 are roots for the degree four expression. The factorization of the equation would be
%28x%2B1%29%28x-2%29%28x%5E2-2x%2B5%29=0 and you would like to find any other REAL roots, because that is what your
question specifies.
The discriminant of the found quadratic factor is %28-2%29%5E2-4%2A5=4-20=-16, negative, therefore x%5E2-2x%2B5 has NO REAL ROOT.

The solution for the original given equation is therefore system%28x=-1%2COR%2Cx=2%29.