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Math Help - circular functions

  1. #1
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    circular functions

    I'm working on a homework assignment for class and I'm really stuck on one. The answers are in the back of the book so I know I'm doing it wrong but I can't figure out where. Thanks!

    evaluate the given expression, leaving the answer in simple radical form. (sec 30)/(cos 30) I keep getting 1 i don't know why.
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  2. #2
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    e^(i*pi)'s Avatar
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    Wrong answer - see post 5
    Last edited by e^(i*pi); March 11th 2011 at 03:09 PM.
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  3. #3
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    so i was right? bc the book says 4/3
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  4. #4
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    Quote Originally Posted by stuckonmath View Post
    (sec 30)/(cos 30) I keep getting 1 i don't know why.
    Because \sec(30)=\dfrac{1}{\cos(30)} we get \dfrac{\sec(30)}{\cos(30)}=\dfrac{1}{\cos^2(30)}.
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  5. #5
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    so i was wrong? what you're saying makes sense but why doesn't it work out when i it the normal way?
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    Quote Originally Posted by stuckonmath View Post
    so i was wrong? what you're saying makes sense but why doesn't it work out when i it the normal way?
    What does the normal way mean?
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  7. #7
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    haha sorry i usually figure out what what they are as is. so sec 30 would be (2 square route 3)/3 and cos 30 is square route of 3/2
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  8. #8
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    e^(i*pi)'s Avatar
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    Yes, so you now have \dfrac{\frac{2\sqrt3}{3}}{\frac{\sqrt{3}}{2}} = \dfrac{2\sqrt3}{3} \times \dfrac{2}{\sqrt3}
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  9. #9
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    You titled this "circular functions" so it seems very strange that you would deal with degrees. In the definition of "circular functions" is not an angle at all- it is a distance around the circumference of the circle. And if you want to interpret it as an angle, you have to set it in radians- the distance around the entire circle of radius 1 is 2\pi.
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