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Exponential formula (complex numbers)?

a^(x+b) + c = 0

Make x the subject.

I got log a (c) + (i*pi/ln(a)) - b = x

Is this correct?

2 Answers

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  • 1 decade ago
    Favorite Answer

    Not quite. If you plug in your solution, you get a^(c ln(a)) + c instead of 0.

    I got the following:

    x = ln(-c) / ln(a) + n*i*pi / ln(a) - b,

    where n is an integer.

    (Assuming of course a, c, and ln(a) are nonzero.)

    I don't have time to write up the details. Sorry. :-(

    Source(s): Degree in Mathematics
  • ?
    Lv 4
    4 years ago

    z^4 + z = 0 z * (z^3 + a million) = 0 z * (z + a million) * (z^2 - z + a million) = 0 this is by way of the reality z^3 + a million is the sum of two cubes (a^3 + b^3) and as such it factors into (a + b) * (a^2 - ab + b^2) z = 0 z + a million = 0 z = -a million z^2 - z + a million = 0 z = (a million +/- sqrt(a million - 4)) / 2 z = (a million +/- i * sqrt(3)) / 2 z = 0 , -a million , (a million/2) * (a million + i * sqrt(3)) , (a million/2) * (a million - i * sqrt(3))

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