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!

Sinusoids homework help

  1. Sep 30, 2007 #1
    1. The problem statement, all variables and given/known data

    Express 8.5sin(290t+325) as C1cos(wt)+C2sin(wt)

    2. Relevant equations

    The previous parts of the problem actually ask to find the wave equation itself and write it in different forms. So the above wave equation can also be expressed as 8.5cos(290t-125) or as -8.5cos(290t+55) etc.

    3. The attempt at a solution

    Can I use the following trig identity: A cos (wt) + B sin (wt) = (A^2 + B^2)^1/2 cos (wt + tan^-1 (-B/A)) ?
  2. jcsd
  3. Sep 30, 2007 #2


    User Avatar
    Science Advisor
    Homework Helper

    It's easier than that. Use sin(a+b)=sin(a)*cos(b)+cos(a)*sin(b).
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Sinusoids homework help
  1. Sinusoids math help (Replies: 5)