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Sin/sec/tan/csc help

  1. Oct 15, 2004 #1
    How do they figure this answer out?

    sin 240 x sec(-45) - tan (-pie/6) csc(-315)

    Basiclaly it says

    sin(240 degrees) times sec(-145 degrees) - tan(-pie/positive 6) csc(-315 degrees)

    says the answer is -square root 6/6

    sorry I dont know how to do the symbol stuff on this forum :( plz forgive me.
  2. jcsd
  3. Oct 15, 2004 #2
    It is not the policy of this site do homework for you. You'll have to figure it out for yourself. I'll give you a hint, however. Change all of the angles into radians, and using reference triangles, just figure out the values of each term directly. (You'll know the ratios because all the triangles are either 30º-60º-90º or 45º-45º-90º triangles). This is the most basic way to do it.

    On a side note, [itex]\pi[/itex] is spelled "pi," not "pie." A pie is something that you eat. Pi is the Greek letter.
    Last edited: Oct 15, 2004
  4. Oct 16, 2004 #3


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    Am I the only one that thinks that a trig problem in which angles are given as both degrees (45) and radians (-pi/6) is really horrible? Especially if there was not mention as to which was which. If I saw "-pi/6" here, why wouldn't I assume that was radians and that "sec -45" means the secant of -45 radians?
  5. Oct 16, 2004 #4


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    It's a blasphemy! :grumpy:
    In addition, the author has evidently not understood that "radian trig functions" are different functions than "degree trig functions", since, given the same input yield different values.
    Last edited: Oct 16, 2004
  6. Oct 16, 2004 #5
    I think the author is just trying to confuse these guys even further. They don't need that.
  7. Oct 16, 2004 #6


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    In that case, he's a sadist; that's even worse than ignorance, IMO.
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