Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

causingaruckus,eh?

  • 3 years ago

Find the norm of vector r prime of t when r(t) = t^2i + 2sintj + 2costk

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

    r'(t)=? r(t) is given

  2. modphysnoob
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    so start with taking derivative

  3. modphysnoob
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    then square each component , add them

  4. modphysnoob
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    take square root

  5. causingaruckus,eh?
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[\sqrt(4t^2 + 4\cos^2t + 4\sin^2t)\]

  6. causingaruckus,eh?
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    What's the trig identity for cos and sin?

  7. modphysnoob
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    cos^2 t + sin^2 t =1

  8. causingaruckus,eh?
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so does the second half of that just become 8?

  9. modphysnoob
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    4( 1)=4

  10. causingaruckus,eh?
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Can you explain? I can never follow this one...

  11. modphysnoob
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    cos(t)^2+sin(t)^2=1 4(cos(t)^2+sin(t)^2)=4

  12. causingaruckus,eh?
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Ohhhh.... Is that technically combining like terms?

  13. modphysnoob
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    I guess

  14. causingaruckus,eh?
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Thanks!

  15. modphysnoob
    • 3 years ago
    Best Response
    You've already chosen the best response.
    Medals 1

    no problem

  16. 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