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

gerryliyana

solve dy/dx = e^{x+y} (x+y)^{-1} - 1 y ????

  • one year ago
  • one year ago

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

    solve what

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

    \[\frac{ dy }{ dx } = e^{x+y} (x+y)^{-1} - 1 \]

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

    dame i am not at a level like this one, i am sorry

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

    ok..., no problem @MikiaseKebede nevermind :)

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

    you should ask http://openstudy.com/users/jim_thompson5910

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

    him

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

    ok

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

    he is good

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

    i think you have to apply the product rule

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

    what did u get it??

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

    hmm i havent solved it just trying to help you with it

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

    or there is another easier way u =x+y du/dx = 1 du =dx

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

    http://mathhelpforum.com/differential-equations/194955-solving-dy-dx-e-x-y.html

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

    solve dy/dx = e^{x+y}

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

    @mayankdevnani No, i mean \[\frac{ dy }{ dx } = e^{x+y} (x+y)^{-1} - 1 \]

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

    let \[z=x+y\]and u have\[\frac{\text{d}z}{\text{d}x}=1+\frac{\text{d}y}{\text{d}x}\]put this in the original equation\[\frac{\text{d}z}{\text{d}x}-1=\frac{e^z}{z}-1\]\[\frac{\text{d}z}{\text{d}x}=\frac{e^z}{z}\]u have a separable differential equation :)

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

    ok @mukushla, then i got \[\int\limits z dz = \int\limits e^{z} dx\] \[\frac{ z^{2} }{ 2 } = e^{z} x\] \[\frac{ (x+y)^{2} }{ 2 } = e^{x+y} x\] Did I miss something?

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

    emm...there is a little mistake in ur separation\[ze^{-z}\text{d}z=\text{d}x\]

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

    \[\int\limits \frac{ z }{ e^{z} } dz = \int\limits dx \]

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

    exactly

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

    \[\frac{ -1 + z }{ e^{z} } = x\] \[\frac{ -1 + x + y }{ e^{x+y} } = x\] \[\frac{ x+y-1 }{ x } = e^{x+y}\]

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

    integration by parts for z :)

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

    \[\int\limits ze^{-z} dz = \int\limits dx\] u = z, \(dv = e^{-z} dz\), then du = dz, and \(v = -e^{-z}\) So \[-ze^{-z} - \int\limits -e^{-z} dz = \int\limits dx\] \[-ze^{-z} - \frac{ e^{-z} }{ \ln e } = x\] then ??

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

    ln e = 1 re substitute z as x+y

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

    \[-ze^{-z} - e^{-z} = x\] \[-(x+y)e^{-(x+y)} - e^{(x+y)} = x\] \[(-x-y - 1) e^{-(x+y)} = x\] \[(1+x+y) =- x e^{(x+y)}\]

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

    did i miss something?

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

    nopes, thats correct. :)

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

    so how to find y?

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

    i don't think, y can be isolated....

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

    http://www.wolframalpha.com/input/?i=%281%2Bx%2By%29%3D%E2%88%92xe%5E%28x%2By%29+solve+for+y

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

    what it means to "W is the product log function"??

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

    even idk that... not a standard function for sure....

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

    ok Thank you all so much! i really appreciate it :)

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

    welcome ^_^

    • 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.