Quantcast

Got Homework?

Connect with other students for help. It's a free community.

  • across
    MIT Grad Student
    Online now
  • laura*
    Helped 1,000 students
    Online now
  • Hero
    College Math Guru
    Online now

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

psk981 Group Title

Evaluate: Please look at the integral

  • one year ago
  • one year ago

  • This Question is Closed
  1. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    \[\int\limits_{C}^{} F.T ds \] for a vector field F=x ^{2}i-yj

    • one year ago
  2. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    from (2,4) to (1.1)

    • one year ago
  3. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    |dw:1352896610110:dw|

    • one year ago
  4. experimentX Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    along the straight line? what is T ?

    • one year ago
  5. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    you have to find flow

    • one year ago
  6. experimentX Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1352897206497:dw|

    • one year ago
  7. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    how did u get r(t) i know you used the points but why did u pick t for the second set of points

    • one year ago
  8. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    the t used is just a variable scalar to stretch the vector to all point along the line from the point used to anchor it to the line

    • one year ago
  9. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    so how would i find F. dr/dt where T=dr/dt?

    • one year ago
  10. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    i dont recall the flow stuff to clearly, but does this look familiar? \[\frac{dr}{dt}=\frac{dr}{dx}\frac{dx}{dt}+\frac{dr}{dy}\frac{dy}{dt}\]

    • one year ago
  11. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    looks like chain rule

    • one year ago
  12. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    this is a line integral right?

    • one year ago
  13. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    http://tutorial.math.lamar.edu/Classes/CalcIII/LineIntegralsVectorFields.aspx ive always found this to be a rather good read. so im going over it

    • one year ago
  14. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    r(t)= <2-t, 4-3t>

    • one year ago
  15. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    F=(2-t)^2i-(4-3t)j

    • one year ago
  16. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    i believe we also need r'

    • one year ago
  17. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    how would i get it i know its a derivative would it be r(t)= -i-3j

    • one year ago
  18. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    r'(t)=-i-3j

    • one year ago
  19. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    then thats its; dot F and r' together to get a scalar equation to integrate right?

    • one year ago
  20. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    yes its F. dr/dt

    • one year ago
  21. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    i am not sure abt the dr/dt part

    • one year ago
  22. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    r= <2-t, 4-3t> r'= <(2-t)', (4-3t)'> r'= <-1, -3>

    • one year ago
  23. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    F=<(2-t)^2 ,-4+3t> dot r'=< -1 , -3 > ----------------------- -(2-t^2)+12-9t

    • one year ago
  24. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    got me ^2 in the wrong side ... :/

    • one year ago
  25. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    the line is from t=0 to t=1 giving us\[\int_{0}^{1}-4-t^2+4t-9t+12~dt\]\[\int_{0}^{1}-t^2-5t+8~dt\]

    • one year ago
  26. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    do you have an answer key to check with by chance?

    • one year ago
  27. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    nope

    • one year ago
  28. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    well, weve followed the simple directions from pauls site; so it should be good ;)

    • one year ago
  29. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    these vector fields so confusing

    • one year ago
  30. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    indeed they are

    • one year ago
  31. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    i have another vector question

    • one year ago
  32. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    the Force equation gives us the force at each for each x,y point along the line the lines vector equation gives us the x and y values along the path F(r) is just defining the forces along the path; dotting with r' tho has me a little baffled at an explanation at the moment tho ;)

    • one year ago
  33. psk981 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    how do i draw a vector field

    • one year ago
  34. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    for each lattice point on a graph you draw a little arrow indicating the direction and magnitude of the vector associated with the values of x and y (or whatever reference frame your using) at that point

    • one year ago
    • Attachments:

See more questions >>>

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.