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    https://983c9f06eb1f75af6e83364e092b...20C4%20OCR.pdf

    For question 2ii we have to find an angle for ABC. The markscheme says AB.BC. However, when I do normal vector questions, I do the vectors coming out of the angle, i.e BA.BC. Why is this one different or do I have the wrong approach?
    Thank you
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    (Original post by snmk007)
    https://983c9f06eb1f75af6e83364e092b...20C4%20OCR.pdf

    For question 2ii we have to find an angle for ABC. The markscheme says AB.BC. However, when I do normal vector questions, I do the vectors coming out of the angle, i.e BA.BC. Why is this one different or do I have the wrong approach?
    Thank you
    Can you pass me the mark scheme?
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    (Original post by ChirMu)
    Can you pass me the mark scheme?
    https://983c9f06eb1f75af6e83364e092b...20C4%20OCR.pdf

    Thanks
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    (Original post by snmk007)
    https://983c9f06eb1f75af6e83364e092b...20C4%20OCR.pdf

    For question 2ii we have to find an angle for ABC. The markscheme says AB.BC. However, when I do normal vector questions, I do the vectors coming out of the angle, i.e BA.BC. Why is this one different or do I have the wrong approach?
    Thank you
    I have checked the two methods and both are correct.
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    (Original post by ChirMu)
    I have checked the two methods and both are correct.
    Thanjks so much, I just did an error in my working
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    (Original post by snmk007)
    Thanjks so much, I just did an error in my working
    You're welcome
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    (Original post by snmk007)
    https://983c9f06eb1f75af6e83364e092b...20C4%20OCR.pdf

    For question 2ii we have to find an angle for ABC. The markscheme says AB.BC. However, when I do normal vector questions, I do the vectors coming out of the angle, i.e BA.BC. Why is this one different or do I have the wrong approach?
    Thank you
    The method you use is the correct one for ALL cases. However, when the angle between 2 lines is 90 or 180 degrees, then options to use the head-to-tail vector approach becomes correct as well. I've attached an image to to show you what I mean.

    Name:  IMG_0300.jpg
Views: 110
Size:  518.2 KB
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    (Original post by RDKGames)
    The method you use is the correct one for ALL cases. However, when the angle between 2 lines is 90 or 180 degrees, then options to use the head-to-tail vector approach becomes correct as well. I've attached an image to to show you what I mean.

    Name:  IMG_0300.jpg
Views: 110
Size:  518.2 KB

    Thanks soo much
 
 
 
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