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    I don't even know where to begin with these questions, they are:

    question 4, a and b: https://imgur.com/a/lX7Aj

    question 5, a and b: https://imgur.com/a/3JQg5

    and question 7, c: https://imgur.com/a/YzDyi

    How do I do them?

    Thank you.
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    (Original post by YourGoddamnRight)
    I don't even know where to begin with these questions, they are:

    question 4, a and b: https://imgur.com/a/lX7Aj

    question 5, a and b: https://imgur.com/a/3JQg5

    and question 7, c: https://imgur.com/a/YzDyi

    How do I do them?

    Thank you.
    4a) AB = OB - OA. This should literally be explained in your book.
    4b) Once you know AB, just find its magnitude in terms of q and set it equal to 2\sqrt{13} and solve for two values of q

    5a) You need to determine the vector CB first. Do this by just considering the fact that CB = CA + AB = -AC + AB. Then use the dot product equation with cosine of the angle.
    5b) Just use the sine equation for the area of the triangle since you know one angle and can determine the lengths of the two adjacent sides.

    7c) Seems that they joined M to C instead of N! Anyway, to show bisection, you need to show that MD=DN=1/2(MN) and also SD=DT=1/2(ST)
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    (Original post by RDKGames)
    4a) AB = OB - OA. This should literally be explained in your book.
    4b) Once you know AB, just find its magnitude in terms of q and set it equal to 2\sqrt{13} and solve for two values of q

    5a) You need to determine the vector CB first. Do this by just considering the fact that CB = CA + AB = -AC + AB. Then use the dot product equation with cosine of the angle.
    5b) Just use the sine equation for the area of the triangle since you know one angle and can determine the lengths of the two adjacent sides.

    7c) Seems that they joined M to C instead of N! Anyway, to show bisection, you need to show that MD=DN=1/2(MN) and also SD=DT=1/2(ST)
    Sorry I was away from computer.

    For 4a, I already did that, but I don't know what it means by "in terms of q", I got -6i + 7j -qj

    for 5a, I had done CB = -AC + AB, I found that CB is -13i +8j. But I don't know what a dot equation is, we haven't done that.
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    (Original post by YourGoddamnRight)
    Sorry I was away from computer.

    For 4a, I already did that, but I don't know what it means by "in terms of q", I got -6i + 7j -qj

    for 5a, I had done CB = -AC + AB, I found that CB is -13i +8j. But I don't know what a dot equation is, we haven't done that.
    "in terms of q" literally just means your answer contains the variable q. So you almost got it, except you subtracted the wrong way round.
    As I said, AB = OB - OA. You did OA - OB

    5a) Sorry, I had initially misread that the angle they wanted was actually \angle ABC instead of \angle BAC. Meaning that you do not even need the vector AB.
    Anyhow, to work out \angle BAC you need to use the formula \displaystyle \mathbf{a} \cdot \mathbf{b}  = |\mathbf{a}||\mathbf{b}| \cos \theta. If you havent covered this, then the alternative is to indeed do use the fact that |BC|^2 = |AB|^2 + |AC|^2 - 2|AB||AC| \cos \theta and hence you would indeed need to find AB as I first had said.
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    Could someone check my answers for questions 4 and 5.
    q4
    https://imgur.com/a/jF5Bc

    q5
    https://imgur.com/a/jF5Bc

    Thanks
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    Hiya, I'm on the last part of Q7 c, or at least near the end, I have done the following:

    https://imgur.com/a/WRvdi

    How do I turn it into a simultaneous equation to solve?

    Thanks.
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    (Original post by YourGoddamnRight)
    Hiya, I'm on the last part of Q7 c, or at least near the end, I have done the following:

    https://imgur.com/a/WRvdi

    How do I turn it into a simultaneous equation to solve?

    Thanks.
    You're aware that you do not need MC right? You need MN. As I said, M is not supposed to be connected to C.
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    (Original post by RDKGames)
    You're aware that you do not need MC right? You need MN. As I said, M is not supposed to be connected to C.
    I'm going to change that. But is the work right, exluding the MC?

    How would I turn it into a simultanious equation?
 
 
 
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