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    Please see attachment for the question. I got an answer of 0.447 but I'm not sure if that's right.
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    (Original post by Stanspam)
    Please see attachment for the question. I got an answer of 0.447 but I'm not sure if that's right.
    Nope. That value is not in the given range if you're talking about the first part?
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    Let Cosx be C, let Sinx be S:

    *rearrange the first equation...

    26C2 = 24S2 + 8 *now replace S2 with { 1 - C2 }

    rearrangeing you get an equation with just C2 which you can solve to find C { which has to be negative for the values stipulated*

    once you have found C it is easy to find S ( which will be positive ).

    then put these values into the second expression.
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    I think this comes out to be -4/7 but I haven't actually written anything down so that might be wrong.

    (Original post by the bear)
    Let Cosx be C, let Sinx be S: *rearrange the first equation... 26C2 = 24S2 + 8 *now replace S2 with { 1 - C2 } rearrangeing you get an equation with just C2 which you can solve to find C { which has to be negative for the values stipulated* once you have found C it is easy to find S ( which will be positive ). then put these values into the second expression.
    Using this method.
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    (Original post by RyanW97)
    I think this comes out to be -4/7 but I haven't actually written anything down so that might be wrong.



    Using this method.
    that is the result i got

    :five: *
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    (Original post by the bear)
    that is the result i got

    :five: *
    Great! At least I haven't forgotten everything from A Levels over the summer!
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    (Original post by RyanW97)
    I think this comes out to be -4/7 but I haven't actually written anything down so that might be wrong.



    Using this method.
    Yeah it does, thanks! I just checked and I divided by the wrong number in one of the steps
 
 
 
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