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    I know how to do the simple binomial expansions, but how would I do something like
    3/2-x. Or 1/(1+x)^2
    I understand that the power will be negative by what do I do with the number above? E.g the 3 in the first example.
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    (Original post by eggfriedrice)
    I know how to do the simple binomial expansions, but how would I do something like
    3/2-x. Or 1/(1+x)^2
    I understand that the power will be negative by what do I do with the number above? E.g the 3 in the first example.
    In the first case multiply the expansion by three - the expansion ought to be completed in the usual manner, so you need to get it in the form (1 + x)^n
    In the second, nothing.
    Do you see why?
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    \displaystyle \frac{3}{2-x}=\frac{3}{2(1-\frac{x}{2})}=\frac{3(1-\frac{x}{2})^{-1}}{2}

    \displaystyle \frac{1}{(1+x)^2}=(1+x)^{-2}
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    (Original post by eggfriedrice)
    I know how to do the simple binomial expansions, but how would I do something like
    3/2-x. Or 1/(1+x)^2
    I understand that the power will be negative by what do I do with the number above? E.g the 3 in the first example.
    so you would get 3(2-x)^-1 but you have to take the 2 out because it must be in the form 1+ax so get 3*1/2(1-x/2) in the second one you simply do (1+x)^-2 and it is multiplied by 1 so it makes no difference.
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    Thanks, I get that now. Another thing I don't understand it's since the power is negative, then what's the sequence number? Like 5 is 1 5 10 10 5 1, but I don't know how to do it for a negative number ):
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    (Original post by eggfriedrice)
    Thanks, I get that now. Another thing I don't understand it's since the power is negative, then what's the sequence number? Like 5 is 1 5 10 10 5 1, but I don't know how to do it for a negative number ):
    You don't do that. Use the expansion provided in your textbook and formula book.
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    (Original post by Mr M)
    You don't do that. Use the expansion provided in your textbook and formula book.
    Kay thanks, got it!
 
 
 
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