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    Hi, I have the question "Solve:

    log_2 (x+1) - log_2 x = log_2 7"

    Which I have in the form:

    log_2 ( \frac{x+1}{x} ) = log_2 7

    \frac {x+1}{x} = 7

    but have no idea what to do to solve for x . This is probably something silly, so forgive my ignorance if so, but it's really annoying me right now...
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    x/x = 1?
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    (Original post by The Muffin Man_)
    \frac {x+1}{x} = 7
    Multiply through by x.
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    multiply through by x.
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    (Original post by The Muffin Man_)
    Hi, I have the question "Solve:

    log_2 (x+1) - log_2 x = log_2 7"

    Which I have in the form:

    log_2 ( \frac{x+1}{x} ) = log_2 7

    \frac {x+1}{x} = 7

    but have no idea what to do to solve for x . This is probably something silly, so forgive my ignorance if so, but it's really annoying me right now...
    Multiply through by x to get x+1=7x and work from there.
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    (Original post by The Muffin Man_)
    Hi, I have the question "Solve:

    log_2 (x+1) - log_2 x = log_2 7"

    Which I have in the form:

    log_2 ( \frac{x+1}{x} ) = log_2 7

    \frac {x+1}{x} = 7

    but have no idea what to do to solve for x . This is probably something silly, so forgive my ignorance if so, but it's really annoying me right now...
    x + 1 = 7x

    6x = 1

    x = \frac {1}{6}
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    (Original post by thegodofgod)
    x + 1 = 7x

    6x = 1

    x = \frac {1}{6}
    Ah, thank you.
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    In case you didn't get it after the fifth time. You multiply through by x.
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    (Original post by The Muffin Man_)
    Ah, thank you.
    No problems
 
 
 
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