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    • Thread Starter
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    Hi all,

    Silly maths question here, hopefully someone can help me out.

    I need to rearrange y = 2Ln(x-1) so that x is the subject, and then square it (^2). I'm doing a Volumes of Revolution question, and I'm absolutely fine with the actual process, just not how to rearrange equations with an Ln present... :o:

    Any help would be greatly appreciated.
    • PS Helper
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    Well remember that \ln A \equiv \log_e A. In C2 you learnt that a=b^n \iff \log_b a = n -- this is what you need to use.

    Start by dividing through by 2, and then just get rid of the logarithm using the rule above.
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    divide both sides by 2, then e both sides, then add 1 to both sides.
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    there are a number of ways to slove this equation
    • Thread Starter
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    Excellent, I knew it'd be dead simple once someone jogged my memory!
    Thanks to you both.
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    (Original post by houseelf)
    Excellent, I knew it'd be dead simple once someone jogged my memory!
    Thanks to you both.
    Congratulations on your 100th post.
    • Thread Starter
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    (Original post by TSR King)
    Congratulations on your 100th post.
    Haha, thanks. I just wish TSR centennials had a positive effect on maths ability...
 
 
 
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