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    How would I solve \cos x=2?
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    You don't :beard:
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    (Original post by Cryptokyo)
    How would I solve \cos x=2?
    I don't think there is a solution because cos(x) can't be bigger than 1 or smaller than -1
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    (Original post by Cryptokyo)
    How would I solve \cos x=2?
    Use

    cos(x+iy) = cosx coshy - i sinx sinhy
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    In which domain?
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    The function cosx only varies between -1 and 1. There is no number that equals arccos(2).
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    (Original post by RichE)
    Use

    cos(x+iy) = cosx coshy - i sinx sinhy
    Thank you!

    Thank you to you too!
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    Don't really know what people would do without you TeeEM :hugs:
    I think this stuff is a bit beyond my level (A2 Maths) XD
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    (Original post by CheeseIsVeg)
    You don't :beard:
    (Original post by anosmianAcrimony)
    The function cosx only varies between -1 and 1. There is no number that equals arccos(2).
    Let's not jump to conclusions so quick
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    (Original post by RDKGames)
    Let's not jump to conclusions so quick
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    Use the exponential definition of cos, you get a quadratic in e^x.
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    (Original post by anosmianAcrimony)
    The function cosx only varies between -1 and 1. There is no number that equals arccos(2).
    The solution is more complex than you realise...
 
 
 
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