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Homework Help: Trig Funtions Problems

  1. Feb 8, 2005 #1
    Im having some problems with some trig function question...im not really understanding what they are asking with these type of questions?

    help please

    determine the larger angle a in the range pie<a<2pie

    sec A = 1.2048

    answer a= (in radians)

    the answer is 5.6915 rads
     
  2. jcsd
  3. Feb 8, 2005 #2
    ok so the question is that we want to determine the larger angle [tex] \alpha [/tex] in the range [tex] \pi < \alpha < 2\pi [/tex]

    Now [tex] \sec x = \frac{1}{\cos x} [/tex] See if you can go from here.
     
  4. Feb 8, 2005 #3
    First, start off by writing secant as a cosine function:

    [tex]\frac{1}{\cos A}=1.2048[/tex]

    Now, solve the function for A. Remember, [itex]\arccos A[/itex] is only defined from 0 to [itex]\pi[/itex] so you have to find a corresponding angle between [itex]\pi[/itex] and [itex]2\pi[/itex]

    good luck.
     
  5. Feb 8, 2005 #4
    yea but how do i put it in radians?
     
  6. Feb 8, 2005 #5

    Doc Al

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    Staff: Mentor

    This question would make more sense if asked about the range from 0 to [itex]2\pi[/itex], since there would be two angles with sec = 1.2048. But there's only one in the range of [itex]\pi[/itex] to [itex]2\pi[/itex], so the question doesn't make that much sense.
     
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