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!

How to determine the point of intersection of sine and cosine?

  1. Mar 14, 2007 #1
    1. The problem statement, all variables and given/known data

    Im not sure how to start this question: determine the points of intersection between [tex]y=sin x[/tex] and [tex]y=cos 2 x[/tex] for x between 0 and pi.

    3. The attempt at a solution

    First thing that comes to mind is the eqaute the two, but i dont know how that helps me?
  2. jcsd
  3. Mar 14, 2007 #2


    User Avatar
    Science Advisor
    Homework Helper

    It should help you. And the identities regarding the sin and cos functions should help you more...
  4. Mar 14, 2007 #3


    User Avatar
    Staff Emeritus
    Science Advisor

    Particularly an indentity that says cos(2x) is equal to something.
  5. Mar 14, 2007 #4
    thanks ive got it now, but is the only point of intersection in the range at [tex]\frac{\pi}{2}[/tex]? i suppose i could graph it to be sure...
    Last edited: Mar 14, 2007
  6. Mar 14, 2007 #5

    Gib Z

    User Avatar
    Homework Helper

  7. Mar 14, 2007 #6
    okay, i was solving incorrectly, they will also both be at [tex]30^{o}[/tex]. i also assumed i would get a "nice" number. thanks.
    Last edited: Mar 14, 2007
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: How to determine the point of intersection of sine and cosine?
  1. Sine and Cosine (Replies: 1)