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Math Help - find the domain of ln(2-5x)

  1. #1
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    find the domain of ln(2-5x)

    ln must operate on a value > 0

    So I solved for the inequality:


    2-5x>0

    x>2/5

    is this right?

    I graphed the function but the domain was x<2/5

    I'm not sure what I'm doing wrong.

    Any help is appreciated.
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  2. #2
    ux0
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    when u divide by (-5) on the inequality, the inequality signs flips so it would be x is less than 2/5 not greater than
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  3. #3
    No one in Particular VonNemo19's Avatar
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    Quote Originally Posted by REWIND10 View Post
    ln must operate on a value > 0

    So I solved for the inequality:


    2-5x>0

    x>2/5

    is this right?

    I graphed the function but the domain was x<2/5

    I'm not sure what I'm doing wrong.

    Any help is appreciated.
    Dividing by a negative number reverses the sign of an inequality.

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  4. #4
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    Thanks so much you guys!
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