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Find the nth roots of the equation?

(z+1)^n = 3 (z+2)^n

I appreciate all help! Thanks in advance.

1 Answer

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  • 6 years ago

    If you took the "n"th root on both sides, you would be left with the roots themselves (as if n=1)

    n=1

    z+1 = 3(z+2)

    z + 1 = 3z + 6

    -5 = 2z

    -5/2 = z

    This (n=1) is what you would have if you took the "n"th root on both sides, in real numbers.

    -----

    If you tried to solve directly for specific values of n, you would begin with small values:

    If n=0 then we have

    1 = 3

    This is not good.

    -----

    n = 2

    z^2 + 2z + 1 = 3(z^2 + 4z + 4)

    z^2 + 2z + 1 = 3z^2 + 12z + 12

    0 = 2z^2 + 10z + 3

    Quadratic formula

    z = [ -10 ± √(100 - 24)¸/ 4

    z = [ -10 ± √(76)] / 4

    z = -5/2 ± √(4.75)

    It seems the value of z depends on the value of n.

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