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    Hi all!

    The question asks you to solve |cosx| >/= sqrt3 / 2 for 0degrees</= x </= 360 degrees.

    I did the following:
    |cosx|>/= sqrt3 / 2 meaning x is 30 degrees
    and |cosx|>/= - sqrt3 / 2 meaning x is 150 degrees.

    They however get x is between 0 and 60, between 120 and 240 and between 300 and 360 (all of those are "or equal to" btw)

    Thanks in advance
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    For  | \cos x | \geq \sqrt 3/2 , I would probably just find the points where  | \cos x | =\sqrt 3/2 and then consider the shape of the curve (do a quick sketch) to find the range of values that satisfy the inequality.
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    (Original post by B_9710)
    For  | \cos x | \geq \sqrt 3/2 , I would probably just find the points where  | \cos x | =\sqrt 3/2 and then consider the shape of the curve (do a quick sketch) to find the range of values that satisfy the inequality.
    I tried to do this but still couldn't get their answers I can't see what I'm doing wrong though
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    (Original post by Blake Jones)
    Hi all!

    The question asks you to solve |cosx| >/= sqrt3 / 2 for 0degrees</= x </= 360 degrees.

    I did the following:
    |cosx|>/= sqrt3 / 2 meaning x is 30 degrees
    and |cosx|>/= - sqrt3 / 2 meaning x is 150 degrees.

    They however get x is between 0 and 60, between 120 and 240 and between 300 and 360 (all of those are "or equal to" btw)

    Thanks in advance
    Have you been assuming (incorrectly) that

    \displaystyle \cos 60 = \frac{\sqrt{3}}{2}

    ?
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    (Original post by notnek)
    Have you been assuming (incorrectly) that

    \displaystyle \cos 60 = \frac{\sqrt{3}}{2}

    ?
    Nope but thanks for the suggestion
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    Name:  image.jpg
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    Basically we are looking for when the blue curve is above or at the same height as the green line.
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    (Original post by B_9710)
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    Basically we are looking for when the blue curve is above or at the same height as the green line.
    Thanks for your help, I think I'll have to do a few more of this type of question to solidify it in my head
 
 
 
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