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Homework Help: Signs of Trignometric Ratios.

  1. Sep 23, 2009 #1
    Identifying the signs of ratio in four quadrants. It turns out that -ive trignometric identity will be negative but not for cos and sec. But why?
  2. jcsd
  3. Sep 23, 2009 #2


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    if you mean why cos(-x)=cos(x)

    is because if you draw x clockwise,it lies in the 4th quadrant and where is cos(x) +ve?
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