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!

Differentiation of Trigonometric functions

  1. Dec 31, 2008 #1
    1. The problem statement, all variables and given/known data
    Let y = tan2(3x-2)
    Find dy/dx


    The solution is:
    2*tan(3x-2)*sec(3x-2)*3
    = 6*tan(3x-2)*sec2(3x-2)

    Why is it not:
    6*tan(3x-2)*sec(3x-2)

    I am thinking:
    y = (tan(3x-2))2
    take the power 2 down,multiply with the parentes multiply with the defferentiated parentes

    Edit: Happy new year
     
  2. jcsd
  3. Dec 31, 2008 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    happy new year!

    Hi MaxManus! Happy new year! :smile:

    (what are parentes? :confused: do you mean "parenthesis"?)

    y = (thing)2,

    so y' = 2(thing)(thing') …

    in this case, the thing is a tan, and tan' = sec2 :wink:
     
  4. Dec 31, 2008 #3

    jgens

    User Avatar
    Gold Member

    What do you think d(tan(u))/dx is equivalent to?

    Edit: tiny-tim beat me to it.
     
  5. Dec 31, 2008 #4

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    happy new year!

    na na na na-na! :tongue:

    hic! :redface:

    :smile: happy new year! :smile:
     
  6. Dec 31, 2008 #5

    jgens

    User Avatar
    Gold Member

    Happy new year! :)
     
  7. Dec 31, 2008 #6
    Thanks tiny-tim and jgens.
    Yes, I ment parenthesis, but I could not spell it.
     
  8. Dec 31, 2008 #7

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    Hitting the champagne a little early?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?