SOLUTION: The rational root of the equation 2x^3-x^2-4x+2=0 is

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Question 966979: The rational root of the equation 2x^3-x^2-4x+2=0 is
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
The rational root of the equation 2x^3-x^2-4x+2=0 is
we can group factor here
rearrange
2x^3 - 4x - x^2 + 2 = 0
factor out 2x and -1
2x(x^2 - 2) - 1(x^2 - 2) = 0
Factor out (x^2-2)
(x^2 - 2)(2x - 1) = 0
Three solutions
x^2 = 2
x = +sqrt%282%29
x = -sqrt%282%29
and
2x = 1
x = 1/2