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    Hi, I asked for help on the maths form in the Scottish Qualification section however I believe that this form will reach more people and faster who can hopefully help me.

    Can someone please help me with this maths homework, I have no clue at all how to do these 3 questions and the homework is for tomorrow so I know it is a lot to ask at this late stage but any help would be much appreciated.



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    I'm unable to read your attachments because they are far too small, could you upload it via imgur or tinpypic or something of that sort?
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    (Original post by Zacken)
    I'm unable to read your attachments because they are far too small, could you upload it via imgur or tinpypic or something of that sort?
    Uploaded to imgur but I don't know if that has made them that much bigger but it is the biggest I can do
    http://imgur.com/VbTJkPf
    http://imgur.com/Gfd9toG
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    (Original post by TartanGibby)
    Uploaded to imgur but I don't know if that has made them that much bigger but it is the biggest I can do
    http://imgur.com/VbTJkPf
    http://imgur.com/Gfd9toG
    Somebody else will have to help, I'm sorry but I can't read anything on them. If you'd like to write the first question out, I could try giving a hand?
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    They are bigger but the picture is too fuzzy


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    (Original post by TartanGibby)
    Uploaded to imgur but I don't know if that has made them that much bigger but it is the biggest I can do
    http://imgur.com/VbTJkPf
    http://imgur.com/Gfd9toG
    Please look at your images before posting them.

    If you're struggling to read them then we have no chance.
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    Question 3
    Prove that √3 cos x + sin x = 2 cos (x - π/6)


    Question 4
    The frequency, f hertz, of the sound of a car alarm t seconds after it starts is given by:
    f = 2500 - 200sin120t° + 200√3cos120t°

    Part A
    Express f in the form f = 2500 + k sin(120t + a)°, where k > 0 and 0° less than or equal to a and less than or equal to 180°

    Part B
    Find the maximum value of f and the first time when this occurs

    Part C
    If the frequency rises above 2800 hertz, the alarm may cause noise pollution. Between which times is the alarm above this frequency.
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    Name:  WIN_20160314_20_32_02_Pro.jpg
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Size:  140.7 KB If you can read and make sense of this then I think these are the answers for q5
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    (Original post by TartanGibby)
    Question 3
    Prove that √3 cos x + sin x = 2 cos (x - π/6)
    Do you know what cos(A - B) is equal to?
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    (Original post by TartanGibby)
    Question 3
    Prove that √3 cos x + sin x = 2 cos (x - π/6)
    Expand 2\cos (x - \pi/6) = 2\cos x \cos \frac{\pi}{6} + 2 \sin x \sin \frac{\pi}{6}.
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    (Original post by NamelessPersona)
    Do you know what cos(A - B) is equal to?
    cos(A - B) = cos A cos B + sin A sin B


    (Original post by Zacken)
    Expand 2\cos (x - \pi/6) = 2\cos x \cos \frac{\pi}{6} + 2 \sin x \sin \frac{\pi}{6}.
    Is that all the working?
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    (Original post by TartanGibby)
    cos(A - B) = cos A cos B + sin A sin B



    Is that all the working?
    Substitute in A=x and B=pi/6 and then you will get your answer after multiplying by 2.
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    (Original post by TartanGibby)
    Is that all the working?
    You'd need to plug in the exact values for \sin \frac{\pi}{6} and \cos \frac{\pi}{6}.
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    Name:  WIN_20160314_20_55_57_Pro.jpg
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Size:  127.3 KBnot so sure about these ones
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    Thank you everyone for your help, it is much appreciated and I think I am starting to understand how to do they sorts of questions now.
 
 
 
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