1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Grade 12 Math - Trigonometry Question.

  1. May 7, 2012 #1
    1. The problem statement, all variables and given/known data

    tanxsinx+sinx=0
    0≤x≤2∏

    What is the largest domain given?

    Problem.

    I'm not sure what to do with this question. It's probably pretty simple, but I'm absolutely rubbish at math. Hopefully someone can help me with this? Thanks.
    -Lily
     
  2. jcsd
  3. May 7, 2012 #2
    Try factoring out a sin from the left side, and use the zero product property to solve.
     
  4. May 7, 2012 #3
    Well it's asking you in the domain 0 to 2pi when is that equation zero. So the first think I would do is pull a sin(x) out of the left hand and then you can split the equation up in two things, with the correct solutions being when either one is zero.
     
  5. May 8, 2012 #4
    So, I'm assuming this?


    tanxsinx+sinx=0
    sinx(tanx + 1) = 0
    sinx = 0
    x = pi
    tanx = -1
    x = 3pi/4 , 7pi/4
     
  6. May 8, 2012 #5

    Mentallic

    User Avatar
    Homework Helper

    Yes, but for [itex]\sin(x)=0[/itex] there are more values of x where this is satisfied.
     
  7. May 8, 2012 #6
    I'm not quite sure I follow?
     
  8. May 8, 2012 #7

    Mentallic

    User Avatar
    Homework Helper

    Remember the domain is [itex]0\leq x \leq 2\pi[/itex]. So where is [itex]\sin(x)=0[/itex] in this domain? Surely more places than just at [itex]x=\pi[/itex]. Take x=0 for example.
     
  9. May 8, 2012 #8
    Oh, I get it! Thanks everyone!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Grade 12 Math - Trigonometry Question.
Loading...