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    9^x=3^x-1
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    (Original post by nadeem7866*)
    9^x=3^x-1
    9^x=3^x-1
    or
    9^x=3^{x-1} ?
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    The second one
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    (Original post by nadeem7866*)
    9^x=3^x-1
    you have to split the 9^ into 3^2x because 3^2 is 9 , then the equation become 3^2x=3^x-1 i think thats how you do it try it
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    And then log both sides and simplify it?
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    Thank you for the help, still not too sure but i got x=-1
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    Posted from TSR Mobile
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    I did plus forget what I sent

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    Yes

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    That was supposed to be in reply to the OP.

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    ffs... pretend I don't exist please

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    Moved to maths

    (Original post by Makadia)
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    (Original post by rayquaza17)
    Moved to maths


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9^x=3^{x-1}

(3^2)^x=3^{x-1}

3^{2x}=3^{x-1}

log_3(3^{2x})=log_3(3^{x-1})

2x=x-1

x=-1

    So you are correct, x=-1.
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    Thanks guys
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    Anybody know how to this..Name:  ImageUploadedByStudent Room1452987879.804950.jpg
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    Question 4 about logs


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    (Original post by nadeem7866*)
    Anybody know how to this..Name:  ImageUploadedByStudent Room1452987879.804950.jpg
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    Have you made a start?
    Remember to use the laws of logs.
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    I got to this and stopped..


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