Posted by Jamie on Monday, March 23, 2009 at 11:58am.
List the possible rational roots of 2x^3 + 17x^2 + 23x  42 = 0
My answer: the possible rational roots are {±1, ±2, ±3, ±6, ±7, ±14, ±21, ±42. ±1/2, ±3/2, ± 7/2, ±21/2}.
Correct?

Advanced Math.  Reiny, Monday, March 23, 2009 at 1:08pm
yes, and guess what?
x = 1 works!
after a quick synthetic division I got
2x^3 + 17x^2 + 23x  42 = 0
(x1)(x^2 + 19x + 42) = 0
and that quadratic factors very nicely again. 
Advanced Math.  Count Iblis, Monday, March 23, 2009 at 1:18pm
Yes, this is what you get when you apply the Rational Roots theorem.
But your list is very long, so it is of little use. It is a bit like answering the question by saying that all possible rational roots are the members of Q (as the problem didn't specifically say to list all the roots that the Rational Roots theorem yields). 
Advanced Math.  Bartolo Windu, Wednesday, October 31, 2012 at 5:30pm
Incorrect