Results 1 to 3 of 3

Math Help - Simplification sine and cosine

  1. #1
    Newbie
    Joined
    May 2008
    Posts
    5

    Simplification sine and cosine

    I've been given a question for an assignment due today and all it says is

    Simplify:

    a) Sin(n*Pi)
    b) Cos(n*Pi)

    Its a computer entered assignment, so i worked out that the answer to part a) is 0, I cant work out b) though. If it helps the assignment topic is on odd/even fourier series. Plz help
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Forum Admin topsquark's Avatar
    Joined
    Jan 2006
    From
    Wellsville, NY
    Posts
    9,933
    Thanks
    336
    Awards
    1
    Quote Originally Posted by martinr View Post
    I've been given a question for an assignment due today and all it says is

    Simplify:

    a) Sin(n*Pi)
    b) Cos(n*Pi)

    Its a computer entered assignment, so i worked out that the answer to part a) is 0, I cant work out b) though. If it helps the assignment topic is on odd/even fourier series. Plz help
    cos(0) = 1

    cos(\pi) = -1

    cos(2\pi) = 1

    cos(3\pi) = -1

    See the pattern?

    -Dan
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Behold, the power of SARDINES!
    TheEmptySet's Avatar
    Joined
    Feb 2008
    From
    Yuma, AZ, USA
    Posts
    3,764
    Thanks
    78
    Quote Originally Posted by martinr View Post
    I've been given a question for an assignment due today and all it says is

    Simplify:

    a) Sin(n*Pi)
    b) Cos(n*Pi)

    Its a computer entered assignment, so i worked out that the answer to part a) is 0, I cant work out b) though. If it helps the assignment topic is on odd/even fourier series. Plz help

    Remember what n stands for n is a natural number i.e 1,2,3,...

    try a few

    \cos(1 \cdot \pi)=-1

    \cos(2 \cdot \pi)=1

    \cos(3 \cdot \pi)=-1

    so the pattern is \cos(n\pi)=(-1)^n
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Sine and Cosine
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: September 9th 2011, 08:40 PM
  2. Cosine and Sine Help
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: November 24th 2009, 07:15 PM
  3. Law of cosine and sine
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: April 15th 2009, 11:39 AM
  4. Cosine/Sine
    Posted in the Trigonometry Forum
    Replies: 2
    Last Post: January 5th 2009, 05:10 PM
  5. cosine and sine..
    Posted in the Calculus Forum
    Replies: 1
    Last Post: November 4th 2008, 12:49 AM

Search Tags


/mathhelpforum @mathhelpforum