Precalculus

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More log/exponential equations

log2 x + log2(x+2) =3

  • Precalculus -

    log2 (x(x+2)) = 3
    x(x+2) = 2^3 = 8
    x^2 + 2x - 8 = 0
    (x+4)(x-2) = 0
    x=2

    throw out x=-4, since logx is not defined for x<0

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