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    I have been attempting to do Question 2 (attached below) and have not been able to get Y = 5N after many attempts. I have watched a YouTube video (attached below) and then tried to answer the question using their technique. My workings are also attached below, so you can identify any errors that I have made along the way.

    All help will be greatly appreciated!

    Question 2:
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    My working:
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    The YouTube video:
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    The first thing I spotted was that -X cos 60 and + X sin 60 don't "cancel out".
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    That's exactly what I thought too.

    I think it was that in the video's example the angle was 45, which is the rare occasion where the sine and cosine of the angle are the same.

    However I do not see how I can find out Y when I do not know the value of X
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    (Original post by x0diak)
    That's exactly what I thought too.

    I think it was that in the video's example the angle was 45, which is the rare occasion where the sine and cosine of the angle are the same.

    However I do not see how I can find out Y when I do not know the value of X
    really? you missed something very big!
    It's very short, fill in the missing angles i.e. between Y and X, you should notice something.
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    I still can't get Y to equal 5 :confused:

    Can you show me the full working and indicate where I went wrong please?
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    (Original post by x0diak)
    I still can't get Y to equal 5 :confused:

    Can you show me the full working and indicate where I went wrong please?
    You've resolved it correctly, but what followed is incorrect (xsin60 is the same as xcos30 but not the same as xcos60).

    Re-arrange your first line to make x the subject of the formula (make x in terms of y) (it might help to know that cos60 = 0.5). Substitute x into your second equation. Take 10 to the other side, factorise the LHS by taking out y and find y.
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    Thank you SO much! You are an absolute life saver!!!
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    (Original post by x0diak)
    Thank you SO much! You are an absolute life saver!!!
    No Problem
 
 
 
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