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

Asylum15

- Integral!

  • one year ago
  • one year ago

  • This Question is Closed
  1. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    \[\int\limits \frac{ lnx }{ x }\]

    • one year ago
  2. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Whos feelin brave? :D

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

    I'm thinking by parts...

    • one year ago
  4. surdawi
    Best Response
    You've already chosen the best response.
    Medals 0

    u du

    • one year ago
  5. Siddharth18
    Best Response
    You've already chosen the best response.
    Medals 0

    do it by substitution, let lnx= u

    • one year ago
  6. TuringTest
    Best Response
    You've already chosen the best response.
    Medals 0

    haha, oh yeah, I overthought it :P

    • one year ago
  7. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Can U be lnx ? It's above the line

    • one year ago
  8. TuringTest
    Best Response
    You've already chosen the best response.
    Medals 0

    so?

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

    |dw:1353166961045:dw|

    • one year ago
  10. Siddharth18
    Best Response
    You've already chosen the best response.
    Medals 0

    |dw:1353035523772:dw|

    • one year ago
  11. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Put ln(x) = u So: \(\frac{1}{x} \cdot dx =du\)

    • one year ago
  12. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Thank you guys

    • one year ago
  13. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Just try and if you face any problem, then do ask us...

    • one year ago
  14. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Wait, can you expand on that for me? I have \[dx = \frac{ du }{ 1/x }\]

    • one year ago
  15. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Are you converting a simple solution to hard one??

    • one year ago
  16. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Looks like it xD

    • one year ago
  17. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    |dw:1353167337486:dw|

    • one year ago
  18. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Sorry, my handwriting is not too good..

    • one year ago
  19. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Is this a direct manipulation or a substitution?

    • one year ago
  20. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Is this not Substitution ?? We are substituting u in place of x..

    • one year ago
  21. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Ah, ok, so lnx. Differentiation of ln = 1 over So 1/x right?

    • one year ago
  22. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Yes..

    • one year ago
  23. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    \[\frac{d}{dx}\ln(x) = \frac{1}{x}\]

    • one year ago
  24. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    So, let me just clarify. lnx / x = 1/x?

    • one year ago
  25. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Where does the x under the line go?

    • one year ago
  26. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    See : \[\ln(x) = u\] Right ??

    • one year ago
  27. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Yes

    • one year ago
  28. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Now take derivative both the sides and tell what did you get??

    • one year ago
  29. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Next, i've been taught to do du/dx

    • one year ago
  30. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    1/x . dx

    • one year ago
  31. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Write them properly.. with LHS and RHS..

    • one year ago
  32. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Little lost here, sorry :(

    • one year ago
  33. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    1/x . dx = du

    • one year ago
  34. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Do you know how it came??

    • one year ago
  35. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    Yes i get this.

    • one year ago
  36. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    What is the next step?

    • one year ago
  37. waterineyes
    Best Response
    You've already chosen the best response.
    Medals 2

    Just use this to substitute these values in your question..

    • one year ago
  38. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    I think the way i've been taught is conflicting... I usually write dx = du / 1/x

    • one year ago
  39. Asylum15
    Best Response
    You've already chosen the best response.
    Medals 0

    If substituting

    • 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.