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Homework Help: Error Analysis

  1. Mar 11, 2007 #1
    1. The problem statement, all variables and given/known data

    I can't seem to find online how to calculate the error propogated by trigonometric functions.

    That is, I know the uncertainty in [tex] \theta [/tex] but am not sure how to deal with it when I apply the tan function.

    I am quite okay with how to deal with all the basic functions w.r.t. error analysis, just not the trig ones.

    2. Relevant equations

    misc * tan(theta)

    3. The attempt at a solution

    Searched the internet.
  2. jcsd
  3. Mar 11, 2007 #2
    First thing come to my mind is to use the Tan(A+B) formula..
    ps:did you try to differentiate?Tan(A+Delt(A))??
    Last edited: Mar 11, 2007
  4. Mar 11, 2007 #3
    what I mean by differentiate is this:
    Tan(x+dx)=Tan'(x)dx + tan(x)
    Edit:the above formula is derived from the definition of derivation, thus the error would be Tan'(x)dx
    Last edited: Mar 11, 2007
  5. Mar 12, 2007 #4


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    Science Advisor

    Minor point: that is true in the limit as dx goes to 0. For non-zero error dx, it is a first order approximation to the error in the function. That's probably what is needed here.
  6. Mar 12, 2007 #5
    Are you asking for propagation of error?
    Have a look at here:
    http://www.rit.edu/~uphysics/uncertainties/Uncertaintiespart2.html#functions2 [Broken]
    Last edited by a moderator: May 2, 2017
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