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    Im completely lost in this question. Ive tried what the mark scheme says yet I still cant get the right answer

    http://thepaperbank.co.uk/papers/AS-...2006_jun_w.pdf
    Question 1b.

    EDIT = Nvm, figured where I went wrong. Didnt add it when using the cosine rule. Although Im still a bit confused. Why add and not subtract since the cosine rule states a^2=b^2+c^2 - 2bcCosA. I getting confused on the minus part of the equation...
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    (Original post by MBT Bot)
    It's been a while since you posted and nobody's replied yet...maybe you should check out MarkedbyTeachers.com, TSR's sister site. It has the largest library of essays in the UK with over 173,000+ coursework, essays, homeworks etc.. all written by GCSE, A Level, University and IB students across all topics.

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    Piss off bot.
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    (Original post by TwlilightLoz)
    Im completely lost in this question. Ive tried what the mark scheme says yet I still cant get the right answer

    http://thepaperbank.co.uk/papers/AS-...2006_jun_w.pdf
    Question 1b.

    EDIT = Nvm, figured where I went wrong. Didnt add it when using the cosine rule. Although Im still a bit confused. Why add and not subtract since the cosine rule states a^2=b^2+c^2 - 2bcCosA. I getting confused on the minus part of the equation...
    The resultant is the vector sum of the two. So you have to move the 16N force such that the head of the 12N force touches the tail of the 16N force. Then the resultant is drawn from the tail of the 12N to the head of the newly moved 16N force.

    Now you have this triangle, the angle in you're cosine rule is no longer 50 degrees, but (180 - 50).

    As cos(180-50) = -cos50, you can see where the sign switch occurs.
 
 
 
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