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Homework Help: General Physics doubt-please help

  1. Sep 2, 2008 #1
    For small angles theta, the numerical value of sin theta is approximately the same as the

    numerical value of tan theta.Find the largest angle for which sine and tangent agree to within

    two significant figures.
  2. jcsd
  3. Sep 2, 2008 #2
  4. Sep 2, 2008 #3
    I'm just learning this myself, but I would make a triangle, with an extremely long adjacent side and plug in values for theta (I think you'll have to find the opposite side for each angle). I'm not really too sure where that would lead, or if it's the right advice, but it's a place to start. Find an angle that is equal to just two (I think) significant figures and then add small increments to theta. Take this advice with a grain of salt though.
  5. Sep 2, 2008 #4
    hmm well basically its saying find the highest value of Ø such as sin(Ø) = tan(Ø) up to the second decimal place. im guessing alot of guessing/checking?
  6. Sep 2, 2008 #5


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    What do you know about the approximations that might lead you to be able to calculate it without guessing about it?

    What is the approximation of

    [tex]Sin\theta \approx \Delta x[/tex]

    [tex]Tan\theta \approx \Delta x[/tex]

    based on?
  7. Sep 2, 2008 #6
    im not sure what you mean
  8. Sep 2, 2008 #7
    i need to submit my assignment by 7 in the morning, so if you could be more clear. Thank You
  9. Sep 2, 2008 #8


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    [tex]Sin x \approx x[/tex]


    [tex]Tan x \approx \ x[/tex]

    [tex]Tan x = \frac{Sin x}{Cos x} \approx \frac{x}{1 - x}[/tex]

    So what is the difference between the 2? That is what you want to identify where the divergence occurs.
  10. Sep 2, 2008 #9
    Im sorry i dont understand what you mean. Im only a freshman its my first assignment. I just dont get it. youve gotta be more clear
  11. Sep 2, 2008 #10


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    This might explain it better than I can.


    I rewrote the previous equations all in x and maybe that will be less confusing.
    Last edited: Sep 2, 2008
  12. Sep 2, 2008 #11


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    In particular this passage:

  13. Jan 14, 2010 #12
    how the letter(ex:a) will be converted into waves?
  14. Jan 14, 2010 #13
    actually u r correct , but when we come to tan values and sin values in degree
    they are same in some region ,so we will concider as same
  15. Jan 14, 2010 #14
    yes you are correct but we will consider them as same values in rare cases and the consideration may nullify some errors.
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