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    • Thread Starter
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    Hello,

    Can anyone help?

    I am working throughEdexcel AS and A level Mathematics Course book and am struggling to understand the answer

    The question is simplify x^3/2 x x^5/2

    The answer give is x^4

    the way they show it work out is x^3/2+5/2

    My question is are they adding the numerators and then dividing it by the denominator

    I have tried to use LaTEX to show the equations but forum wont accept them images when copied in.
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    (Original post by medavidcook)
    Hello,

    Can anyone help?

    I am working throughEdexcel AS and A level Mathematics Course book and am struggling to understand the answer

    The question is simplify x^3/2 / x^5/2

    The answer give is x^4

    the way they show it work out is x^3/2+5/2

    My question is are they adding the numerators and then dividing it by the denominator

    I have tried to use LaTEX to show the equations but forum wont accept them images when copied in.
    Their working and answer are incorrect. When two numbers with the same base are divided, the indices subtract.

    So, here it would be \dfrac{x^{3/2}}{x^{5/2}} = x^{3/2 - 5/2}

    Also, not sure I understand your question.
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    Not sure how they get x^4, it should be x^-1. When dividing, you simply subtract the powers.
    • Thread Starter
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    Hello,

    Can anyone help?

    I am working throughEdexcel AS and A level Mathematics Course book and am struggling to understand the answer

    The question is simplify x^3/2 x x^5/2

    The answer give is x^4

    the way they show it work out is x^3/2+5/2

    My question is are they adding the numerators and then dividing it by the denominator

    I have tried to use LaTEX to show the equations but forum wont accept them images when copied in.
    • Thread Starter
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    Sorry made an error amended post
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    (Original post by medavidcook)
    ...
    No need to create two of the same thread...
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    (Original post by RDKGames)
    No need to create two of the same thread...
    Sorry tried to amend the other one but created a new one, but i cant delete it
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    (Original post by medavidcook)
    Sorry made an error amended post
    OK, in which case they're correct.

    For addition of fractions, we have \frac{a}{c} + \frac{b}{c} = \frac{a+b}{c} since the denominators are the same. This is a basic rule from GCSE.
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    (Original post by medavidcook)
    Sorry tried to amend the other one but created a new one, but i cant delete it
    I merged them for you.
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    (Original post by RDKGames)
    OK, in which case they're correct.

    For addition of fractions, we have \frac{a}{c} + \frac{b}{c} = \frac{a+b}{c} since the denominators are the same. This is a basic rule from GCSE.
    Thank you thought so but couldn't get my head around it
 
 
 
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