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    if i have say:

    e^x + k = y

    why am i not allowed to do:
    take ln of both sides to get: x +lnk = lny


    but instead must do:
    e^x= y -k
    x=ln(y-k)
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    Well, say you have:

    10 = 7 + 2

    You can't do:

    ln 10 = ln 7 + ln 2, try it - it doesn;t work.

    If it did, then I could solve fermat's last theorum!

    a^n + b^n = c^n

    ln a + ln b = ln c

    How can this possible be right?


    It's liek squaring both sides - you must put both sides in brackets them do it:

    5 = 2 + 3
    but
    25 =/= 4 + 9
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    (Original post by mik1a)
    Well, say you have:

    10 = 7 + 2

    You can't do:

    ln 10 = ln 7 + ln 2, try it - it doesn;t work.
    not a good example lol...as 10 does not equal 7+2 anyway
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    (Original post by lgs98jonee)
    not a good example lol...as 10 does not equal 7+2 anyway
    darn... 7+2 = 10
    not far off though.
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    that is quite funny....
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    (Original post by mik1a)
    Well, say you have:

    10 = 7 + 2

    You can't do:

    ln 10 = ln 7 + ln 2, try it - it doesn;t work.

    If it did, then I could solve fermat's last theorum!
    Argh, theorem damn it.
 
 
 
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Updated: June 16, 2004
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