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

inkyvoyd Group Title

Integrate \(\Huge \frac{x}{ax^2+bx+c}\)

  • 2 years ago
  • 2 years ago

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

    Linear by Quadratic...

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

    Eh?

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

    But, how exactly am I supposed to do this one?

    • 2 years ago
  4. waterineyes Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    If you put ax2 + bx + c = y then it helps or not??

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

    uhh... what about the top - we just substitute using the quadratic formula in that case?

    • 2 years ago
  6. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Sorry guys, I'm not even sure where to start with this integral. I can't find it in my book either >.<

    • 2 years ago
  7. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    bring everything on the bottom to the top... then integration by parts?

    • 2 years ago
  8. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    uhh - I'm not sure that will work >.<

    • 2 years ago
  9. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    why not...

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

    All the related integrals had something to do with trig sub and inverse trig functions, but i can't find this case.

    • 2 years ago
  11. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    ohh

    • 2 years ago
  12. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    I know what the answer is (from an integral table), and it's logarithmic+trigonometric. I have no idea where to start though

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

    http://integral-table.com/downloads/single-page-integral-table.pdf #16, btw

    • 2 years ago
  14. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    ahhh that got me thinkin... let me take another look

    • 2 years ago
  15. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    well log came from 1/x

    • 2 years ago
  16. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Yes.

    • 2 years ago
  17. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    that looks like a big u sub

    • 2 years ago
  18. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Uh, got any ideas where to start htough?

    • 2 years ago
  19. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    one sec

    • 2 years ago
  20. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    kay

    • 2 years ago
  21. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    just by the looks w/o really thinking about it, it looks like they let the bottom = u

    • 2 years ago
  22. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    then factor out a 2a

    • 2 years ago
  23. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    1/2a *

    • 2 years ago
  24. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    wait wtf

    • 2 years ago
  25. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    lol nvm i thought the second half was the next step

    • 2 years ago
  26. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    thats a tricky one i need a piece of paper for that one lol

    • 2 years ago
  27. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    okay lol. Thanks for helping :P

    • 2 years ago
  28. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    http://www.wolframalpha.com/input/?i=int+x%2F+%28ax2+%2B+bx+%2B+c%29

    • 2 years ago
  29. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    that way is crazzyyyy tho lol

    • 2 years ago
  30. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    lol - but the answer is different from the integral table :S the result is too complicated lol. I'm using some constants for the integral that will make it even more nasty x.x

    • 2 years ago
  31. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    its the same just written different

    • 2 years ago
  32. experimentX Group Title
    Best Response
    You've already chosen the best response.
    Medals 3

    x = 1/2(2x + b/a) - 1/2 (b/a) make two fractions ... and use the usual approach

    • 2 years ago
  33. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    ^^^ thats what w.a did too

    • 2 years ago
  34. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Okay. any way to reduce it to the form seen in the integral table?

    • 2 years ago
  35. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    probably not

    • 2 years ago
  36. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    once i substitute my values in, it is still an intermediate result - I still have to do two more substitutions, and I'm not sure I can do the algebra without going insane.

    • 2 years ago
  37. experimentX Group Title
    Best Response
    You've already chosen the best response.
    Medals 3

    one is going to be log another ... complete squares (a+sqrt(b/4a))^2 - (b/4a-c)

    • 2 years ago
  38. experimentX Group Title
    Best Response
    You've already chosen the best response.
    Medals 3

    this is in standard form ... you should be able to evaluate this.

    • 2 years ago
  39. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Wait, I can do it by completing the square as well?

    • 2 years ago
  40. experimentX Group Title
    Best Response
    You've already chosen the best response.
    Medals 3

    \[ \frac1{2a}\frac{x + b/a}{x + b/a x+c/a} - \frac1{2a}\frac{ b/a}{(x + \sqrt{b/4a})^2 - (b/4a-c/a)}\]

    • 2 years ago
  41. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    oh wow. this integral - sqrt(tan x) - is a freaking pain...

    • 2 years ago
  42. experimentX Group Title
    Best Response
    You've already chosen the best response.
    Medals 3

    quite a bit ... assuming c/a > b/4a

    • 2 years ago
  43. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    yea just about all realistic functions are either extremely tedious or impossible to solve by hand. When it comes to practical application, we usually just have computers solve or approximate the solution.

    • 2 years ago
  44. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Ugh, I give up. I'm tired of this integral lol. I'll look into it more tomorrow. Thanks though, @experimentX and @eyust707

    • 2 years ago
  45. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    thats when the mathematicians come in handy =P

    • 2 years ago
  46. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    yw inky.. you taking calc 2 over the summer??

    • 2 years ago
  47. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    I'm trying to finish calc 3 and linear algebra and diff equations over the summer >.<

    • 2 years ago
  48. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    crazyyy

    • 2 years ago
  49. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    that is a lot of material to learn!!

    • 2 years ago
  50. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Yea, hopefully I can finish it.

    • 2 years ago
  51. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    I got faith!! where about are you in diffs?

    • 2 years ago
  52. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    Haven't even started LOL

    • 2 years ago
  53. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    haha I see I see

    • 2 years ago
  54. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    well, I skimmed the variables seperatble and the first order linear ODE I think

    • 2 years ago
  55. experimentX Group Title
    Best Response
    You've already chosen the best response.
    Medals 3

    It's just a substitution ... reduces to the form \[ \int \frac1 {x^2 + a^2}dx\] or, \[ \int \frac 1{x^2 - a^2}dx\] assuming first, wolf calculates 2/a arctan(x/a)

    • 2 years ago
  56. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    yea seps will seem very natural

    • 2 years ago
  57. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    linear first order with the integrating factor is tricky to understand at first... but easy to do

    • 2 years ago
  58. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    youll prob see frustrating word problems but dont let them scare you.. they always work out to be quite simple

    • 2 years ago
  59. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    alright - I have to learn how to integrate these nasty partial fractions first though haha :P

    • 2 years ago
  60. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    haha just remember, If your integrating with respect to y , all the other variables are constant!

    • 2 years ago
  61. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    keep repeating that in your head as you run through your derivative..

    • 2 years ago
  62. eyust707 Group Title
    Best Response
    You've already chosen the best response.
    Medals 1

    pretend that all the other letters are just numbers and youll be golden!

    • 2 years ago
  63. dpaInc Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    didn't you see what i last posted earlier inky?

    • 2 years ago
  64. inkyvoyd Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    uhh what did you post?

    • 2 years 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.