SOLUTION: How do I solve this, I'm very confused... x^3-3x^2+6x+10=0

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Question 983343: How do I solve this, I'm very confused...
x^3-3x^2+6x+10=0
Answer by josgarithmetic(39621) About Me  (Show Source):
You can put this solution on YOUR website!
Rational Roots Theorem; synthetic division trying roots -1,-2,-5,1,2,5; maybe +10 or -10. 


-1   |   1   -3   6   10
     |       -1   4   -10
     _____________________
         1   -4   10   0 -------- highlight%28-1%29 is a (real) root.

Now use quadratic equation skills to get the two other roots.


x%5E2-4x%2B10=0-----comes from the quotient of the previous synthetic division.

x=%284%2B-+sqrt%2816-4%2A10%29%29%2F2

x=%284%2B-+sqrt%284%284-10%29%29%29%2F2

x=%284%2B-+2sqrt%28-6%29%29%2F2

x=2%2B-+sqrt%28-6%29

highlight%28x=2%2B-+i%2Asqrt%286%29%29-----these are the two complex roots.

FINISHED.
Degree of equation is three; so only three roots.