A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • one year ago

I really appreciate the help! How do I find sin(11pi/3)? I might have a pop quiz tomorrow and I really need help to figure this out. Thanks!

  • This Question is Closed
  1. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    @ganeshie8 @Michele_Laino @zepdrix @Luigi0210 @Compassionate @Whitemonsterbunny17 @adrynicoleb @Xmoses1

  2. Compassionate
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    \[\sin \frac{ 11 \times 3.14 }{ 3 }\]

  3. Xmoses1
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I wish i would have paid attention in high school...

  4. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    @Compassionate but how do I calculate it? I know the answer is sqrt(2)/2.

  5. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    @Compassionate I think there is a graph method, but I don't get it.

  6. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Someone help please ;_;

  7. Michele_Laino
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    hint: \[\Large \frac{{11\pi }}{3} = 3\pi + \frac{{2\pi }}{3}\] then we have to use the formula of addition for "sin" function

  8. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    what is that?

  9. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Is it sinacosb+sinbcosa?

  10. Michele_Laino
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    yes! \[\Large \begin{gathered} \sin \left( {\frac{{11\pi }}{3}} \right) = \sin \left( {3\pi + \frac{{2\pi }}{3}} \right) = \hfill \\ \hfill \\ = \sin \left( {3\pi } \right)\cos \left( {\frac{{2\pi }}{3}} \right) + \cos \left( {3\pi } \right)\sin \left( {\frac{{2\pi }}{3}} \right) = ...? \hfill \\ \end{gathered} \]

  11. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I don't really understand where to go from there.

  12. Michele_Laino
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    it is simple, we have these values: \[\Large \begin{gathered} \sin \left( {3\pi } \right) = 0 \hfill \\ \cos \left( {\frac{{2\pi }}{3}} \right) = - \frac{1}{2} \hfill \\ \cos \left( {3\pi } \right) = - 1 \hfill \\ \sin \left( {\frac{{2\pi }}{3}} \right) = \frac{{\sqrt 3 }}{2} \hfill \\ \end{gathered} \] please substitute them into my formula above

  13. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    -sqrt(3)/2

  14. Michele_Laino
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    hint: \[\Large \begin{gathered} \sin \left( {\frac{{11\pi }}{3}} \right) = \sin \left( {3\pi + \frac{{2\pi }}{3}} \right) = \hfill \\ \hfill \\ = \sin \left( {3\pi } \right)\cos \left( {\frac{{2\pi }}{3}} \right) + \cos \left( {3\pi } \right)\sin \left( {\frac{{2\pi }}{3}} \right) = \hfill \\ \hfill \\ = 0 \cdot \left( { - \frac{1}{2}} \right) + \left( { - 1} \right) \cdot \left( {\frac{{\sqrt 3 }}{2}} \right) = ...? \hfill \\ \end{gathered} \]

  15. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    yup, thanks for the help!

  16. Michele_Laino
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 2

    :)

  17. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Hopefully I can ace the pop quiz if it is tomorrow! :D Now to sleep.

  18. anonymous
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[\sin(n\pi+\theta)=(-1)^n.\sin(\theta) \forall n \in \mathbb{Z}^+\mathbb{Z}^-\]

  19. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.