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

UnkleRhaukus Group Title

question about notation

  • one year ago
  • one year ago

  • This Question is Closed
  1. UnkleRhaukus Group Title
    Best Response
    You've already chosen the best response.
    Medals 2

    in my book there is a question involving a term like this \[\int\limits_p^\infty F(p)\cdot\text dp \], but this is a confusing choice of notation because the variable of integration is one one of limits of integration

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

    as far as i know the convention is to change to \[\int\limits_p^\infty F(p')\cdot\text dp'\] but i dont like this because it looks like the prime of p

    • one year ago
  3. ash2326 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    As we know that integration is independent of variable. You could use any variable of your choice. I'd go with the first one :)

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

    a?

    • one year ago
  5. ash2326 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    yes

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

    \[\int\limits_p^\infty F(a)\cdot\text da\]

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

    \[\int\limits_p^\infty F(x)\cdot\text dx\]

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

    \[\int\limits\limits_p^\infty F(mukushla)\cdot\text d(mukushla)\]

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

    • one year ago
    1 Attachment
  10. UnkleRhaukus Group Title
    Best Response
    You've already chosen the best response.
    Medals 2

    the notation is still troubling me

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

    Where???

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

    well i kinda had to change the question so i could answer it

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

    \[\begin{align*} \int\limits_p^\infty F(q)\cdot\text dq &=\int\limits_p^\infty\int\limits_0^\infty f(x)e^{-qx}\cdot\text dx\cdot\text dq \\&=\int\limits_0^\infty f(x)\int\limits_p^\infty e^{-qx}\cdot\text dq\cdot\text dx \\&=\int\limits_0^\infty f(x)\left.\frac{e^{-qx}}{-x}\right|_p^\infty \cdot\text dx \\&=\int\limits_0^\infty \frac{f(x)}xe^{-px}\cdot\text dx \\&=\mathcal L\left\{\frac {f(x) }x \right\} \end{align*}\]

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

    do you understand why i am getting confused/

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

    The things you are doing are going above my head, but I am not understanding why are you getting confused, where are you not feeling comfortable??

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

    well the question in the book makes no sense

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

    @sasogeek

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

    certainly this is confusing, but why not use u-substitution for F(p) ?

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

    like this? \[\begin{align*} \int\limits_p^\infty F(p)\cdot\text dp\\ \text{let }u=p\\ \text du=\text dp\\ \\p=p\rightarrow u=u\\ p=\infty\rightarrow u=\infty\\ \\&=\int\limits_u^\infty F(u)\cdot\text du\\ \end{align*}\]

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

    \(let \ u=F(p)\) \(\large \frac{du}{dp}=F'(p)\) \(\large dp =\frac{du}{F'(p)} \) \[\int\limits_{p}^{\infty}u \ \frac{du}{F'(p)}\]

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

    im not sure why you'd do that?

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

    well having the function variable being the same as one of the limits... i'm not quite sure how you'd go about solving it but thats the first thing that comes to my mind. besides, i'm not so good at calculus, but that's what i'd do. it may or may not be right, but it's worth a shot :/. I'm pretty certain this isn't calculus 1... right?

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

    differential equations; laplace transforms

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

    there we go, that's beyond me lol, but all things being equal, thats what i'd do. sorry i wasn't of much help lol :/ but i'll stick around to learn :)

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

    but the problem im having is not the content of the question, i think i have answered that satisfactorily , my issus is the choice of notation used in the question

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

    i dont think the question makes sense as written \[....=\int\limits_p^\infty F(p)\text dp\] it dosent make sense to have the variable as a limit of integration

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

    you could ask satellite73 or amistre when they get online....

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

    @amistre64

    • one year ago
  29. amistre64 Group Title
    Best Response
    You've already chosen the best response.
    Medals 0

    yeah, i looked at this earlier and dont have anything pertinent to add to it :/ srry

    • 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.