Recent content by LHS

  1. L

    How do I show the series of an*bn converges?

    So say something like an=i^n/n^0.5 and bn=an=-i^n/n^0.5 Excellent! that seems to work, thank you very much, now I can finally go to sleep
  2. L

    How do I show the series of an*bn converges?

    thank you very much for your time, I will do that :)
  3. L

    How do I show the series of an*bn converges?

    how about 0<=(a-b)^2 2ab<=a^2+b^2 2ab<=a^2+b^2 therefore 2*sum(ab)<=sum(a^2)+sum(b^2) Where the RHS converges As the LHS converges absolutely sum(ab) converges? Any ideas about the examples? [PLAIN]http://img35.imageshack.us/img35/9916/unledis.png this is from a past...
  4. L

    How do I show the series of an*bn converges?

    Homework Statement [PLAIN]http://img11.imageshack.us/img11/4384/unledqr.png Homework Equations The Attempt at a Solution How do I show the series of an*bn converges?
  5. L

    Suitable change of variables for this triple integral?

    Thanks :) It is annoying when they set questions where there just seems to be some arbitrary factorization which you can spend hours on and learn relatively little from. Have a good day!
  6. L

    Suitable change of variables for this triple integral?

    -(x+y-z)^2-(x-y+z)^2-(-x+y+z)^2 Then let r=x+y-z s=... seems to work! Thanks though!
  7. L

    Suitable change of variables for this triple integral?

    Hmm.. yes I have covered some of that, but nothing I can see that'll help in this situation. the question seems to be wanting you to use a Jacobian etc.. maybe involving the first part
  8. L

    Suitable change of variables for this triple integral?

    Homework Statement [PLAIN]http://img542.imageshack.us/img542/5600/unledsn.png Homework Equations The Attempt at a Solution The first part is fine, just struggling to find a change of variables that'll help, tried spherical due to the x^2+y^2+z^2, didn't help enormously Thanks! (from sheet...
  9. L

    Volume integral, how do I find the limits for my integral?

    ok.. so considering limits for dx,dy,dz z is between a and b y is between a^2/z and b^2/z but what could be do for x?
  10. L

    Volume integral, how do I find the limits for my integral?

    I tried the substitution of X=yz, Y=xy, Z=xz I came out with an answer, but it was extremely messy, due to the Jacobian
  11. L

    Volume integral, how do I find the limits for my integral?

    So does this imply that z<x<z, therefore x=z?
  12. L

    Volume integral, how do I find the limits for my integral?

    Homework Statement [PLAIN]http://img9.imageshack.us/img9/4537/unledow.png Homework Equations The Attempt at a Solution Hi, does anyone know how to find the integral that needs to be evaluated here? I can't understand how to find it from the region edit: Oh and this is from here, not a take...
  13. L

    Complex numbers: how do I show unique solution?

    Homework Statement [PLAIN]http://img689.imageshack.us/img689/6294/08052011193408.jpg Homework Equations The Attempt at a Solution Hi, I would really appreciate some help on part a, I'm simply getting no where. This is classed as a geometry question, but I haven't covered...
  14. L

    Probability question involving recurrence relations

    solved!
  15. L

    Probability question involving recurrence relations

    Homework Statement [PLAIN]http://img812.imageshack.us/img812/5261/unleduqi.png Homework Equations The Attempt at a Solution Can anyone help with part (a)ii, is pk=(1/2)^k? I can't see how to find qk