A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 5 years ago

Write (sin13+sin167+cos13+cos167)(sin13-sin167+cos13-cos167) in the form asinx. No calculators. I used the calculator and got 0. But without it, I can't get the answer to equal 0. I'm up to: 4sin13cos13, which by the reduction formula, equals 4sin13sin77 but then what? ...

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

    oh nevermind! there's the sinAcosB formula

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

    and sin^2A+cos^2A = 1 formula

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

    wait, that still doesn't get me 0

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

    of course it does. expand and see.

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

    I still don't get it.. what am I supposed to do with that formula?

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

    are you sure that the original expression is equal to zero?

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

    oh... that's rather stupid of me. i don't know how to use a calculator. i think i got it this time. by sinAcosB formula, it comes down to 2sin26, which equals the right answer.. this time. Thank you so much everyone!

  8. 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.