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    Really thought vector questions couldn't get harder than the previous ones I had done. I'm stuck on part a) i understand that the i component of the walker is 6i but I can't seem to work out the j component, also the direction of the walker to the mast is i + j. In the mark scheme I don't understand where 6j came from :confused: any help would be appreciated

    EDIT:
    I got the same answer by increasing i and j component by 1 until 6i was reached so i got

    0i + 2j
    1i + 3j
    ...
    6i + 8j

    Is it okay if i write it as 2j + n(i + j) = 6i + aj ? Is there a better way than this thank you
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    We know that the person is at (6,x) for some x, because he's on the pipeline. Also, the person sees something at (0, 2) as being southwest - that is, the mast is at (6,x) + (-y,-y) for some y, because something which is southwest of you is at (-1, -1)k for some k.
    Hence (6,x)+(-y,-y)=(0,2) and so y = 6, x = 8. This tells us that the person is at (6,8) and that the vector from him to the mast is (-6,-6).
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    (Original post by Smaug123)
    We know that the person is at (6,x) for some x, because he's on the pipeline. Also, the person sees something at (0, 2) as being southwest - that is, the mast is at (6,x) + (-y,-y) for some y, because something which is southwest of you is at (-1, -1)k for some k.
    Hence (6,x)+(-y,-y)=(0,2) and so y = 6, x = 8. This tells us that the person is at (6,8) and that the vector from him to the mast is (-6,-6).
    Is my method ok 2j + n(i + j) = 6i + Xj. Not sure if i can always do this
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    (Original post by .raiden.)
    Is my method ok 2j + n(i + j) = 6i + Xj. Not sure if i can always do this
    Yep, your method is pretty much exactly what mine is - I just expanded my explanation a bit (I find that narrative is easier to understand than raw equations). In this kind of question, you'll always be able to do this.
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    (Original post by Smaug123)
    Yep, your method is pretty much exactly what mine is - I just expanded my explanation a bit (I find that narrative is easier to understand than raw equations). In this kind of question, you'll always be able to do this.
    Thanks yes I see what you mean
 
 
 
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