J jhon13 New member Joined May 23, 2012 Messages 9 May 23, 2012 #1 It is known that x^2 + x^-2 and x^3 + x^-3 are integers. Prove that x + x^-1 is also an integer.
L lookagain Elite Member Joined Aug 22, 2010 Messages 3,250 May 23, 2012 #2 jhon13 said: It is known that x^2 + x^-2 and x^3 + x^-3 are integers. Prove that x + x^-1 is also an integer. Click to expand... jhon13, do not post a problem for our consideration without showing your work first.
jhon13 said: It is known that x^2 + x^-2 and x^3 + x^-3 are integers. Prove that x + x^-1 is also an integer. Click to expand... jhon13, do not post a problem for our consideration without showing your work first.