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: Signals and Systems [Calc the Fundamental Period]

  1. Apr 14, 2010 #1
    1. The problem statement, all variables and given/known data
    Determine the Fundamental Period and Frequency

    I got this question wrong on My midterm and I was wondering if you guys could give me some feedback on it

    x(t) = cos[50(pi)t] + sin[15(pi)t]

    2. Relevant equations

    T(fundamental Period) = 2(pi)/w // w is the frequency


    3. The attempt at a solution
    I tried finding the peirod of both sine and cosine

    for first T = 2(pi)/50(pi) = 1/25
    for second T=2(pi)/15(pi) = 2/15

    then you have to find the least common Multiple(I think this is where I messed it up)

    I got for (1/25) and (2/15) LCM to be 1/75 [ like I said I think this is wrong, I'm not sure how to do LCM with fractions]

    I got T=1/75 (fundamental Period)
    then I got W=2(pi)/T = 150(pi0
    and then I got TWO big Xs on them :(
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted