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Math Help - Logarithmic Equation

  1. #1
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    Logarithmic Equation

    Logarithmic equation, missed lecture this day. I just need to know how you go about solving these problems. Thank you so much!

    ln(x+5)+ln(x−5)=0
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  2. #2
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    Quote Originally Posted by thebristolsound View Post
    Logarithmic equation, missed lecture this day. I just need to know how you go about solving these problems. Thank you so much!

    ln(x+5)+ln(x−5)=0
    ln(a)+ln(b) = ln(ab)

    <br />
ln[(x+5)(x-5)] = 0
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  3. #3
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    so from (x+5)(x-5) would I then make the other side e^0 giving me 1?

    Does (x+5)(x-5) become x^2-25?
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  4. #4
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    Quote Originally Posted by thebristolsound View Post
    so from (x+5)(x-5) would I then make the other side e^0 giving me 1?

    Does (x+5)(x-5) become x^2-25?
    Yes and Yes (it's the difference of two squares) so you get x^2-26=0. As 26 is 2*13 it will no break down to be simpler than \sqrt{26}
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