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    http://i.imgur.com/Vclwxot.png


    I understand what happens do the denominator, but I think the numerator is the wrong way around ?

    thanks
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    No the denominator is negative after opening the brackets which results in a fraction that then gets turned upside down to multiply the F.

    The - then swaps things round in the numerator to make it look better.
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    (Original post by jon2016)
    http://i.imgur.com/Vclwxot.png


    I understand what happens do the denominator, but I think the numerator is the wrong way around ?

    thanks
    Nopes, look at the denominator, it is 1 - 1 - \frac{i}{100} = -\frac{i}{100}.

    Hence, \displaystyle \frac{F}{-\frac{i}{100}} = \frac{-100F}{i}

    But then you swap the numerator to get red of the negative sign, i.e: distribute it.
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    (Original post by ghostwalker)
    Looks fine.

    Denominator evaluates to minus i/100.

    Hence the bit in large square brackets is flipped round.
    ah damn I forgot its 1- * ( )
    Rather than just 1 -


    So denominator equals - i/100

    next I multiply it by F ? to get

    -100f/i ?

    then somehow the negative coefficient of -100f/i goes into the numerator ?
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    (Original post by jon2016)
    ...
    -(a-b) = b-a
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    (Original post by Zacken)
    Nopes, look at the denominator, it is 1 - 1 - \frac{i}{100} = -\frac{i}{100}.

    Hence, \displaystyle \frac{F}{-\frac{i}{100}} = \frac{-100F}{i}

    But then you swap the numerator to get red of the negative sign, i.e: distribute it.
    ah thanks clearer know

    so the next stage is multiplying the numerator by -1 ?

    which gives us -1 + ( )^n

    then this can be rearranged as

    ()^n -1 ? how come you can just swap them like that ?
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    (Original post by jon2016)
    ah thanks clearer know

    so the next stage is multiplying the numerator by -1 ?

    which gives us -1 + ( )^n

    then this can be rearranged as

    ()^n -1 ? how come you can just swap them like that ?
    See my above post.
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    (Original post by jon2016)
    ah thanks clearer know

    so the next stage is multiplying the numerator by -1 ?

    which gives us -1 + ( )^n

    then this can be rearranged as

    ()^n -1 ? how come you can just swap them like that ?
    Because you are multiply through the bracket by the -1 i.e. -(x^n-1)=-x^n+1=1-x^n

    Is that what you are asking?
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    (Original post by nerak99)
    Because you are multiply through the bracket by the -1 i.e. -(x^n-1)=-x^n+1=1-x^n

    Is that what you are asking?

    I was confused because I thought

    -1(1 - (1+x)^n) would equal = -1 + (1+x)^n) rather than (1+x)^n) -1 but I guess they are just rearranging it ?

    like

    -1 + 2 is the same as 2 + -1
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    (Original post by Zacken)
    -(a-b) = b-a

    In this example

    a= 1 and b = (1+ i/100)^n ?
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    (Original post by jon2016)
    In this example

    a= 1 and b = (1+ i/100)^n ?
    Yep.
 
 
 
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