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Further maths- manipulating expressions involving alpha and beta watch

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    Hi guys, I dont get this at all! Can someone explain the method on manipulating in laymans terms please?
    Question: write each of the following expressions in terms of alpha+beta and alphabeta
    a)

    2/alpha + 2/beta

    b)
    1/alpha^2beta + 1/beta^2 alpha

    please help!

    Thanks!
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    Put the fractions over a common denominator.
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    (Original post by Unbounded)
    Put the fractions over a common denominator.
    I know that bit, but I dont get what happens to the numerator..
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    (Original post by lionking)
    I know that bit, but I dont get what happens to the numerator..
    times 2/alpha by beta/beta and 2/beta by alpha/alpha...

    come on this is pre-gcse maths
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    (Original post by didgeridoo12uk)
    times 2/alpha by beta/beta and 2/beta by alpha/alpha...

    come on this is pre-gcse maths
    Lol i get that! Im talking about manipulation of alpha and beta -.-.

    Sorry if Im not being clear enough, I thought i was.
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    (Original post by lionking)
    Lol i get that! Im talking about manipulation of alpha and beta -.-.

    Sorry if Im not being clear enough, I thought i was.
    well write out what you have so far

    use latex if you can, it makes it soo much easier to read

    for example

     \frac{g}{ \frac{t+4}{c}+r} = \int_3^{8.5} \! t^{ \frac{2r+c}{g^2}} \, dr.

    and other such ridiculous equations would be illegible written otherwise
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    Ok this is the original question:

    \dfrac{2}{\alpha} + \dfrac{2}{\beta}

    This is what I get after cross multiplying:

    \dfrac{2\alpha+2\beta}{\alpha\be  ta}

    After that I dont know what to do lol.

    For the second question. Original question:

    \dfrac{1}{\alpha^2\beta} + \dfrac{1}{\beta^2\alpha}
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    Yes, so, multiply the first fraction by \frac{\beta}{\beta} and the 2nd fraction by \frac{\alpha}{\alpha}.

    What do you get?
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    (Original post by lionking)
    Ok this is the original question:

    \dfrac{2}{\alpha} + \dfrac{2}{\beta}

    This is what I get after cross multiplying:

    \dfrac{2\alpha+2\beta}{\alpha\be  ta}

    After that I dont know what to do lol.

    For the second question. Original question:

    \dfrac{1}{\alpha^2\beta} + \dfrac{1}{\beta^2\alpha}
    1) Factorise one number out and you are home.

    2) Common denominator of (alpha beta)^2 perhaps?
 
 
 
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