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    well im having quite alot of trouble doing questions like these could someone give me some insight into how they should be done thank you!

    A function f(x) is known to be of the form F(x)=Acos(px+q) + B. It has a local maximum at (6, 8) and the next local minimum is at (10, 2). Find the constants A, p, q and B and hence give the formula for the function.
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    Draw the graph of the cosine function. What is the maximum value that cos(px+q) can take? So what is the maximum value that A*cos(px+q) can take? So what is the maximum value that A*cos(px+q) can take?
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    The graph of \cos x has a maximum at (0, 1) and a minimum at \left( \pi, -1 \right)... what transformations might you be able to apply to the graph of y = \cos x to map these to the points (6,8) and (10,2), respectively?
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    How do you find the stationery point of a function? You're given co-ordinates of the minimum point and maximum point so you can work backwards when considering first and second derivatives to find the values of the constants.
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    a=3 b=5 these correct?
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    (Original post by nuodai)
    The graph of \cos x has a maximum at (0, 1) and a minimum at \left( \pi, -1 \right)... what transformations might you be able to apply to the graph of y = \cos x to map these to the points (6,8) and (10,2), respectively?
    a=3 b=5 these rite?
 
 
 
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