Results 1 to 2 of 2

Math Help - Trig Integration

  1. #1
    Newbie
    Joined
    Jul 2008
    Posts
    8

    Trig Integration

    I attempted the following problem: Integral of sin2xcos3xdx

    and could not do it. After looking at the answer (typed below) Im kicking myself in the butt trying to figure out how they came up with this answer. What identities were used? Can someone help me?

    The following is straight from the solutions manual:

    Integral of sin2xcos3xdx
    half the Integral of (sin5x-sinx)dx
    Answer= -.1cos5x+.5cosx+C
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    Joined
    Jun 2009
    From
    United States
    Posts
    676
    Thanks
    19
    Quote Originally Posted by HELLMACH View Post
    I attempted the following problem: Integral of sin2xcos3xdx

    and could not do it. After looking at the answer (typed below) Im kicking myself in the butt trying to figure out how they came up with this answer. What identities were used? Can someone help me?

    The following is straight from the solutions manual:

    Integral of sin2xcos3xdx
    half the Integral of (sin5x-sinx)dx
    Answer= -.1cos5x+.5cosx+C
    The following identity can split the product into a sum:
    2sin(A)cos(B)=sin(A+B)+sin(A-B)

    It's one of the product formulae in trigonometry.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Another trig sub integration
    Posted in the Calculus Forum
    Replies: 1
    Last Post: September 20th 2009, 05:58 AM
  2. Another u-sub/trig integration
    Posted in the Calculus Forum
    Replies: 16
    Last Post: September 16th 2008, 10:35 PM
  3. Trig Integration
    Posted in the Calculus Forum
    Replies: 1
    Last Post: February 20th 2008, 03:21 PM
  4. Trig integration
    Posted in the Calculus Forum
    Replies: 3
    Last Post: February 16th 2008, 06:10 PM
  5. trig integration help!
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: January 24th 2008, 05:46 PM

Search Tags


/mathhelpforum @mathhelpforum