Results 1 to 3 of 3

Math Help - Trig Help

  1. #1
    Newbie
    Joined
    Mar 2009
    Posts
    8

    Trig Help

    sin(x)=(1/Square root of 10) and pie/2 < X < pie

    cos(x)= ?
    tan(x)= ?
    sec(x)= ?
    csc(x)= ?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    is up to his old tricks again! Jhevon's Avatar
    Joined
    Feb 2007
    From
    New York, USA
    Posts
    11,663
    Thanks
    3
    Quote Originally Posted by jrose011 View Post
    sin(x)=(1/Square root of 10) and pie/2 < X < pie

    cos(x)= ?
    tan(x)= ?
    sec(x)= ?
    csc(x)= ?
    you can use the formula \sin^2 x + \cos^2 x = 1 to find \cos x. once you have that, you can find all others. take note of the quadrant the angle is in, it will dictate the signs the trig functions take.

    alternatively, construct a right triangle. knowing that sine = opposite/hypotenuse, you can call one of the acute angles in the triangle x, the hypotenuse of the triangle must be \sqrt{10}, while the side opposite x must be 1. you can use Pythagoras' theorem to figure out the other side length. once you have all sides filled out, you can use the trig ratios to find your answers: cos(x) = adjacent/hypotenuse, tangent = sine/cosine = opposite/adjacent, etc

    again, watch the signs
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor
    Joined
    Mar 2007
    Posts
    1,240

    Talking

    Quote Originally Posted by jrose011 View Post
    sin(x)=(1/Square root of 10) and pie/2 < X < pie
    I think you mean ``\pi/2\, <\, x\, <\,\pi"...? (A "pie" is a pastry; my favorite is Dutch apple. The number "pi" is approximately 3.14159.)

    Last edited by Jhevon; March 17th 2009 at 08:11 AM. Reason: fixed LaTeX
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Compute Trig Function Values, Solve Trig Equation
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: September 8th 2011, 08:00 PM
  2. Replies: 7
    Last Post: April 15th 2010, 09:12 PM
  3. Replies: 6
    Last Post: November 20th 2009, 05:27 PM
  4. Replies: 1
    Last Post: July 24th 2009, 03:29 AM
  5. Trig Equations with Multiple Trig Functions cont.
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: April 7th 2008, 06:50 PM

Search Tags


/mathhelpforum @mathhelpforum