Question 1154822
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First try all integer divisors of the constant term 2, i.e. +/-1 and +/-2.




Or use the grouping method


x^3 − 2x^2 − x + 2 = (x^3-2x^2) - (x-2) = x^2*(x-2) - (x-2) = (x^2 -1)*(x-2) = (x-1)*(x+1)*(x+2).


All rational zeroes are 1, - 1 and -2.
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