1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Derivatives of trigonometric functions

  1. Jul 28, 2008 #1
    1. The problem statement, all variables and given/known data
    I'm learning now about darivative all by my self (without a teacher) and I'm not sure about this development

    2. Relevant equations

    3. The attempt at a solution



    [tex]{\Delta}Y=senx*cos{\Delta}x+ sen{\Delta}x*cosx[/tex]

    What about this cos,what is it doing in the equation?
    I really don't get it.
  2. jcsd
  3. Jul 28, 2008 #2
    Re: Derivative

    this comes from the double angle formula.

    it says that: sin (A + B) = sinAcosB + sinBcosA

    you can find the same thing for sin (x + dY)
  4. Jul 28, 2008 #3
    Re: Derivative

    Oh,now I think i get it!
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Derivatives of trigonometric functions
  1. Trigonometric Function (Replies: 2)

  2. Trigonometric function (Replies: 6)