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Math Help - Calculate : x/y

  1. #1
    Super Member dhiab's Avatar
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    Calculate : x/y

    If :  2Ln(x-2y)=Ln(x)+Ln(y)
    Find : \frac{x}{y}
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  2. #2
    MHF Contributor
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    Quote Originally Posted by dhiab View Post
    If :  2Ln(x-2y)=Ln(x)+Ln(y)
    Find : \frac{x}{y}
    2L(x-2y)=Lnx+Lny

    2x-4y=nx+ny

    2x-nx=ny+4y

    x(2-n)=y(4+n)

    x/y=(4+n)/(2-n)
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  3. #3
    Super Member dhiab's Avatar
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    Quote Originally Posted by mathaddict View Post
    2L(x-2y)=Lnx+Lny

    2x-4y=nx+ny

    2x-nx=ny+4y

    x(2-n)=y(4+n)

    x/y=(4+n)/(2-n)
    Hello
    Ln(x) is not : Lnx
    Ln(x) is Log
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  4. #4
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    Quote Originally Posted by dhiab View Post
    If :  2Ln(x-2y)=Ln(x)+Ln(y)
    Find : \frac{x}{y}
    Oh ,

    2\ln (x-2y)=\ln x+\ln y

    (x-2y)^2=xy

    x^2-5xy+4y^2=0

    (x-4y)(x-y)=0

    x-4y=0\Rightarrow \frac{x}{y}=4

     <br />
x-y=0\Rightarrow \frac{x}{y}=1<br />
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  5. #5
    Super Member dhiab's Avatar
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    HELLO mathaddict
    The case x = y is impossibl
    Know x>0 , y>0 , x-2y>0
    Conclusion x>2y
    x >y
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  6. #6
    MHF Contributor
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    Quote Originally Posted by dhiab View Post
    HELLO mathaddict
    The case x = y is impossibl
    Know x>0 , y>0 , x-2y>0
    Conclusion x>2y
    x >y
    hey dhiab, yeah of course , i miss that . Thanks dude .
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