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    The question asked me to use the substitution u=x1/2 and on the mark scheme it leads to the expression I have boxed and placed a question mark. Can someone please explain how the fraction can simplify and lead to that expression? Thanks.
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    (Original post by MSB47)
    The question asked me to use the substitution u=x1/2 and on the mark scheme it leads to the expression I have boxed and placed a question mark. Can someone please explain how the fraction can simplify and lead to that expression? Thanks.
    Divide the numerator and the denominator by u
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    (Original post by TenOfThem)
    Divide the numerator and the denominator by u
    How is it possible to do that? Sorry I've gone complete brain dead over this :confused:
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    (Original post by MSB47)
    How is it possible to do that? Sorry I've gone complete brain dead over this :confused:
    Every term in that fraction contains a u.

    \dfrac{u}{u^2+u} = \dfrac{u(1)}{u(u+1)} \equiv \dfrac{1}{u+1}

    Just cancel one u from every term. What Ten' said.
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    (Original post by Phichi)
    Every term in that fraction contains a u.

    \dfrac{u}{u^2+u} = \dfrac{u(1)}{u(u+1)} \equiv \dfrac{1}{u+1}

    Just cancel one u from every term. What Ten' said.
    ohh that makes a lot of sense now, thanks for your help
 
 
 
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