Calculus

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Find the solution of the logarithmic equation:
ln(x+8)+ln(x–8)=0

Im not sure how to approach this one. I tried moving the ln(x-8) to the other side and solving for x and that did not work. I also tried putting everything as an exponent to e. please help! thanks

  • Calculus -

    that is ln of product
    ln (x^2-64) = 0
    e^ln anything = anything
    so
    x^2-64 = e^0 = 1
    x^2 -65 = 0
    x = +/- sqrt 65
    but ln of negative is undefined
    so
    x = +sqrt(65)

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