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    I have the fraction  \frac{2x-1}{\sqrt {5+2x}} .

    Now, I have the solution to the binomial expansion of  \frac{1}{\sqrt{5+2x}} , and I need to use it to find the solution to the formerly mentioned fraction. I believe I could do this if I understood how to get this fraction in a form similar to the first, or in the form (a+bx)^n . The problem lies in the fact that I don't know how to do this when both the numerator and denominator of the fraction are algebraic. Could explain how I would convert this?
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    (Original post by Illidan2)
    I have the fraction  \frac{2x-1}{\sqrt {5+2x}} .

    Now, I have the solution to the binomial expansion of  \frac{1}{\sqrt{5+2x}} , and I need to use it to find the solution to the formerly mentioned fraction. I believe I could do this if I understood how to get this fraction in a form similar to the first, or in the form (a+bx)^n . The problem lies in the fact that I don't know how to do this when both the numerator and denominator of the fraction are algebraic. Could explain how I would convert this?
    The expansion you're looking for is (2x-1) times the one you've already found.

    So, if you have a +bx+cx^2 +dx^3..., multiplying by 2x-1 we have (2x-1)(a +bx+cx^2 +dx^3...) and simply expand the brackets.
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    (Original post by ghostwalker)
    The expansion you're looking for is (2x-1) times the one you've already found.

    So, if you have a +bx+cx^2 +dx^3..., multiplying by 2x-1 we have (2x-1)(a +bx+cx^2 +dx^3...) and simply expand the brackets.
    Of course! Now that you've said it, it's become so clear. Can't believe I missed something so obvious. Thank you!
 
 
 
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