## Is this cublc polynomial function solvable?

Here is a very difficult cubic polynomial.

x^3 - x - 2 = 0

I am wondering whether it is solvable or not. Please think about it.
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 I need help with this too I posted a similar one and haven't got a response... mine was x^3 + 9x -1=0...They are solvable, but I don't know how to get an answer algebraically or graphically.
 EDIT: Deleted totally misleading answer. Ignore if you read it.

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## Is this cublc polynomial function solvable?

 Quote by davedave Here is a very difficult cubic polynomial. x^3 - x - 2 = 0 I am wondering whether it is solvable or not. Please think about it.
 Quote by aew782 I need help with this too I posted a similar one and haven't got a response... mine was x^3 + 9x -1=0...They are solvable, but I don't know how to get an answer algebraically or graphically.
Are they solvable? Let's have a guess: The first one can be tested for divisibility by x+1, x-1, x+2, and x-2. The second one can be tested for divisibility by x+1 and x-1. The results may be faster if you know synthetic division.

 Quote by symbolipoint Are they solvable? Let's have a guess: The first one can be tested for divisibility by x+1, x-1, x+2, and x-2. The second one can be tested for divisibility by x+1 and x-1. The results may be faster if you know synthetic division.
Thank you that's all I needed!
 Recognitions: Homework Help You can use synthetic division, but isn't it simpler to just evaluate the polynomial and see if the equation is satisfied?
 Mentor Blog Entries: 8 Every cubic equation is solvable. You can always use the cubic root algorithm: http://en.wikipedia.org/wiki/Cubic_f...ano.27s_method
 Recognitions: Homework Help The first binomial rendering zero remainder is (x-2). The quotient is x^2+2x+1 which is (x+1)^2. No need to use Cardano's or Vietas substitution for this cubic (micromass gave a good reference Wikipedia article).

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