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    So i have this question X satisfies the equation x^2=3x-1
    I then showed that x+x^-1 =3
    then i expanded (x+x^-1)^2
    and then i expanded (x+x^-1)^3
    Then the question says hence find the values of x^2 +x^-2 and x^3+x^-3
    What do i do?

    When you got to X+x-¹=3, multiply by x, then take away 3x, so you'll have x²-3x+1=0

    Factorise that then find two X values that will equal 0. You might have to use the quadratic equation to find X, I haven't worked it out. When you have two values of X, sub each into the final equations as you stated.
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Updated: February 20, 2018

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