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    Can you bound sin(theta) and cos(theta) above by theta? (For all real values of theta?)


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    Or just for some values?


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    Good luck bounding cos(theta) or sin(theta) by theta above when theta is < -1...

    Also, when theta = 0, cos(theta) = 1, so...
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    cos(theta)<|theta|+1

    Same works for sin.
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    (Original post by james22)
    cos(theta)<|theta|+1
    Not true when theta = 0... (And "beaten" by cos(theta) <= 1 as an inequality anyhow...
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    Any conclusive answer?



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    (Original post by number23)
    Any conclusive answer?
    The answer to your original question is "No (you can't bound sin theta or cos theta by theta for all values of theta)".

    However, this is so blindingly obvious that I suspect what you think you are asking and what I think you are asking are not the same thing...
 
 
 
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