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    For part C) I don't understand why

    \vec{EY} = \vec{EB} + \frac{2}{3} \vec{AB}

    Why is it not \vec{EB} + \frac{2}{5} \vec{AB}

    Because ratio is 2:3
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    Because with the given ratios BY: AB = 2 : 3.

    For AY, we would have BY : AY = 2: 5, which is probably what you are thinking of.
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    (Original post by atsruser)
    Because with the given ratios BY: AB = 2 : 3.

    For AY, we would have BY : AY = 2: 5, which is probably what you are thinking of.
    The way I understood it is total is over 5 (2+3) so AB : 2/5 and BY is 3/5.
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    (Original post by uer23)
    The way I understood it is total is over 5 (2+3) so AB : 2/5 and BY is 3/5.
    That's almost correct but AB is longer so AB = 3/5, BY=2/5. so \frac{BY}{AB} = \frac{2/5}{3/5} = \text{?}
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    (Original post by atsruser)
    That's almost correct but AB is longer so AB = 3/5, BY=2/5. so \frac{BY}{AB} = \frac{2/5}{3/5} = \text{?}
    Apologies, yes sorry I meant the other way round.

    Thanks but can you explain why did you \frac{BY}{AB} = \frac{2/5}{3/5} ?
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    I'm just asking because I done an example earlier where it was slightly different to this



    \vec{PT} = \frac{2}{3}(b-a)

    \vec{TQ} = \frac{1}{3}(b-a)
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    (Original post by uer23)
    I'm just asking because I done an example earlier where it was slightly different to this



    \vec{PT} = \frac{2}{3}(b-a)

    \vec{TQ} = \frac{1}{3}(b-a)
    Ther you have a point within the vector

    On the original it was outside the vector


    In the original if AB had been 3c what would BY have been?
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    (Original post by TenOfThem)
    Ther you have a point within the vector

    On the original it was outside the vector


    In the original if AB had been 3c what would BY have been?
    Oh okay, that makes sense. So for the original question the BY has been extended from original vector ?

    2c ?
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    (Original post by uer23)
    Oh okay, that makes sense. So for the original question the BY has been extended from original vector ?

    2c ?
    Yes
 
 
 
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