solve sec(x) = - 5

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  1. Macromolecular's Avatar
    • Full Member
    • Posts: 93
    solve sec(x) = - 5
    Hi,

    To solve sec (x) = (-) 5 you would have to look at it as 1/cos (x) = -5 then doing cos (x) = - 0.2 but I'm not sure what you do from here to find all the values between the interval 0<x>2(pi) in radians

    Anyone help please?

    Thanks
  2. electriic_ink's Avatar
    • TSR Demigod
    • Location: London
    • Posts: 5,668
    Re: solve sec(x) = - 5
    cos (2pi - x) = cos x
  3. raheem94's Avatar
    • TSR Demigod
    • Posts: 5,512
    Re: solve sec(x) = - 5
    (Original post by Macromolecular)
    Hi,

    To solve sec (x) = (-) 5 you would have to look at it as 1/cos (x) = -5 then doing cos (x) = - 0.2 but I'm not sure what you do from here to find all the values between the interval 0<x>2(pi) in radians

    Anyone help please?

    Thanks
     cosx = -0.2 \implies x = cos^{-1} (-0.2) = \ldots

    Now using the method(i.e. cast/graphs/general solutions) you prefer, find the other solutions in the given range.
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