Quantcast

A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

kenneyfamily

  • 2 years ago

MAJOR HELP PLEASE!! Verify that the equation is an identity. Show all your work. (sin x + cos x)^2 - 1 = sin 2x

  • This Question is Closed
  1. nubeer
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    (a+b)^2 =a^2+2ab+b^2 so (sin x + cos x)^2 - 1 sin^2x+2sinxcosx+cos^2x -1 2sinxcosx +sin^2x+cos^2x -1 i think u can do from here.

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

    use formula \[(a+b)^{2} = a^{2} + 2ab + b^{2}\], expand that out and you will see what you need to

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

    @nubeer i'm sorry i am a little lost, could you please explain further?

  4. nubeer
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    2sinxcosx +sin^2x+cos^2x -1 have you understood how i have got this part?

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

    yes with the formula right?

  6. nubeer
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    2sinxcosx +sin^2x+cos^2x -1 what is sin^2x+cos^2x = ?

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

    1?

  8. nubeer
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    yes.. now put this 1 in the equation 2sinxcosx +sin^2x+cos^2x -1 2sinxcosx +1-1.. got it?

  9. nubeer
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    @kenneyfamily so?

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

    2sinxcosx

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

    @nubeer right?

  12. nubeer
    • 2 years ago
    Best Response
    You've already chosen the best response.
    Medals 2

    yes and 2sinxcosx=sin2x (according to the identity)

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

    you're awesome..thanks!!!

  14. 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.