Results 1 to 4 of 4

Math Help - how do i evaluate...

  1. #1
    Junior Member
    Joined
    Sep 2008
    Posts
    35

    how do i evaluate...

    f(x)=2sinx=8cos(1/2)x???
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member Matt Westwood's Avatar
    Joined
    Jul 2008
    From
    Reading, UK
    Posts
    824
    Thanks
    33
    By plugging in the values of x you're interested in, surely?
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Sep 2008
    Posts
    35
    at x=pi/6
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Super Member Matt Westwood's Avatar
    Joined
    Jul 2008
    From
    Reading, UK
    Posts
    824
    Thanks
    33
    pi/6 is 30 degrees.

    So it's 2 times sin (30 degrees) minus 8 times cos (15 degrees).

    But I'm assuming a level of mathematics which is higher than just looking stuff up in tables yeah? In which case you might want to try the half-angle formulae to express that cos in terms of things which have pi/6's in so you can use the standard values of sin and cos of pi/6. Have fun.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. evaluate
    Posted in the Algebra Forum
    Replies: 4
    Last Post: April 18th 2010, 12:16 PM
  2. evaluate
    Posted in the Calculus Forum
    Replies: 3
    Last Post: November 21st 2009, 03:26 AM
  3. Evaluate
    Posted in the Pre-Calculus Forum
    Replies: 1
    Last Post: January 26th 2009, 04:56 AM
  4. Please evaluate
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: December 14th 2007, 04:36 PM
  5. Evaluate
    Posted in the Calculus Forum
    Replies: 1
    Last Post: December 3rd 2007, 02:21 AM

Search Tags


/mathhelpforum @mathhelpforum