1. Limited time only! Sign up for a free 30min personal 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!

Homework Help: Derivative of trig functions

  1. Mar 2, 2013 #1
    1. The problem statement, all variables and given/known data

    y = √sinx


    3. The attempt at a solution

    y' = [(sinx)1/2]'
    y' = 1/2 (sinx)-1/2 (sinx)'
    y' = 1/2 cosx (sinx)-1/2

    However book says the answer should be:

    1/2 cotx (√sinx)
     
  2. jcsd
  3. Mar 2, 2013 #2
    Hint: what is the definition of cotan(x)?
     
  4. Mar 2, 2013 #3

    Dick

    User Avatar
    Science Advisor
    Homework Helper

    Your answer is right. The book's answer is also right. cot(x)=cos(x)/sin(x). Try to convince yourself they are both right.
     
  5. Mar 2, 2013 #4
    1/tanx ?
     
  6. Mar 2, 2013 #5
    And what is tan in terms of cos and sin?
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted