Ask Me Help Desk

Ask Me Help Desk (https://www.askmehelpdesk.com/forum.php)
-   Math & Sciences (https://www.askmehelpdesk.com/forumdisplay.php?f=402)
-   -   Trig equations (https://www.askmehelpdesk.com/showthread.php?t=22095)

  • Mar 2, 2006, 10:12 PM
    Sami A
    trig equations
    solve the following for 0 is less than or equal to x which is less than or equal to 2pie
    sinxcscx-cscx+2sin=0
  • Mar 3, 2006, 08:51 PM
    dmatos
    First thing to do - try to simplify this equation. Note that cscx = 1/sinx:

    sinxcscx = 1

    1 - 1/sinx + 2sinx = 0

    Well, this looks like it could become a fairly simple quadratic equation with a bit of manipulation. Multiply both sides of the equation by sinx. Then, let y=sinx, and you should see a nice quadratic equation in y.

    Solve the quadratic equation for y (you'll get 2 answers). Then, you have sinx = y. Solve this (I believe the numbers are straightforward - use the inverse trig functions on the calculator if you don't recognize the values). I'm pretty sure the two possible values for y give me three possible values for x that lie between 0 and 2pi (mmm... pie... )

    Hope that helps!

  • All times are GMT -7. The time now is 06:53 AM.